Editor’s note: Justin has previously written at The Hardball Times, among other outposts of the baseball internet, including The Good Phight and Baseball Prospectus. He’ll now add contributing to FanGraphs to that list. We’re excited to welcome him.

This dance only has a couple moves, and they go like this:

One partner, the coach, mutters or shouts an invitation for the other partner, the umpire, to dance with him. The umpire should not — and likely won’t — accept.

Not at first.

He must listen, certainly, and he must hear. He must register every mean or vile thing that comes out of the coach’s mouth. But he must also not hear them. Because it is not time to make his move.

Not yet.

It’s still the coach’s turn to dance. He flails his arms. He stomps his feet. And then, finally, the umpire makes two moves — the only two he’s got.

The first one can be a few things: A whisper. A head cock. Maybe a request for the coach to dance a little longer. Just one more step. Just one more word. Just so the ump can see if he’ll do it.

And if the coach obliges, the ump makes his other move.

He points up and out at the horizon, and tells the coach the dance is over. He can go off somewhere in the direction the ump just pointed. It doesn’t matter where. But he’s got to go now. Because the dance is done, even though the music’s still playing.

With all the chest-pounding, finger-pointing, eye-bulging, and hands-on-hipping we see from major league umpires, it can appear a less graceful, a less coordinated dance than it actually is. But down in the little leagues, all of the mental alertness and situational awareness umpiring requires can be, by necessity, more clearly on display. Read the rest of this entry »

Ronald Acuña Jr., with 34 home runs, 28 stolen bases, and six weeks left in the season, has a chance to become the fifth player to join Major League Baseball’s 40-40 Club. If Acuña’s membership application is approved by feats of baseballing, he’ll join an exclusive fraternity of Jose Canseco, Alex Rodriguez, Barry Bonds, and Alfonso Soriano. Okay, mostly elite.

As someone who apparently became a “veteran” baseball analyst at some point, I’m not always sure if the game has changed or if I have. When I was a kid, there’d be talk of 20-20 clubs, 30 HR/100 RBI guys, and scores of home run milestones. But you don’t hear about these baseball clubs as often as you used to. Has fandom changed this much or have I become jaded about these kinds of statistically interesting accomplishments? Or is that some of the older markers for performance, such as the 400 Homer Club, have become less exclusive institutions to join than a sandwich shop that give you a 10th sub free after buying nine?

The 40-40 Club, on the other hand, still excites me. Part of it could be that Jose Canseco’s charge on his way to becoming the founding member of this fraternity in 1988 was still very early in my Serious Baseball Fandom phase. I’ve loved watching baseball from the age of three, but it wasn’t until a few years later I really became a serious fan of the game, aided by my grandfather getting me a subscription to Sports Illustrated in 1986, a bit before my eighth birthday. While I watched the 1983-1985 World Series games, the 1986 World Series was the first one where I really followed every pitch, watching to the end even on school nights. I can still remember Tim Teufel‘s error as much as Bill Buckner‘s more famous one, and am able to exactly replicate Marty Barrett‘s closed stance and Sid Fernandez’s three-quarters delivery.

Read the rest of this entry »

While the Twins going home run-crazy in a world of home run-wackiness may have been the most significant early storyline for Minnesota, one of the team’s other early bright spots was the emergence of Martín Pérez. I was extremely skeptical of the decision to bring him in given his history with the Rangers, and thought the Twins ought to have been more aggressive in signing top free agents after clearing Joe Mauer’s salary.

In the early months of the season, my worries about Pérez seemed almost quaint. On May 23, at what I would call his high-water mark, the Twins outslugged the Angels, winning 16-7 and leaving Pérez with a 7-1 record and a 2.95 ERA. He was showing increased velocity. Pérez was never a big fastball pitcher, but his increased velocity from late 2018 — when he had an average velocity of at least 95 mph in four of his September relief appearances — continued in 2019 as a starter. But perhaps the most important factor in his early-season success was the development of his cut-fastball, a pitch he picked up on advice from his agent and with help from teammate Jake Odorizzi.

The proof of the pudding is in the eating and with his fancy new cutter, Pérez feasted on opposing batters in the late spring. Through the literal end of the season (June 20), Pérez threw 435 cutters, making it his most-used pitch, and held batters to a .164 BA and a .250 SLG. Against all other pitches, including his fastball, the league was hitting .301. 42% of his 74 strikeouts were thanks to his cutter. To put how well the cutter was performing in perspective, from 2007 on Mariano Rivera, who knows a bit about this pitch, had batters swing-and-miss on 10% of his cutters. Through mid-June, Pérez was at 15%. Read the rest of this entry »

Baseballs are flying in the major leagues this season. Due to a few irregularities on the outer surface of the ball, everything hit in the air is carrying much farther, all else being equal, than at any point in the game’s history. Home runs are up 15% from 2018 and hitters are on pace to shatter the league’s record for dingers in a season.

As many of you also know, Triple-A teams are playing with the same ball. Previously, all minor league teams used a different, less expensive model, one with a flight pattern that more closely resembles the pre-2015 major league pelota. This year, while all other levels still play with the cheaper model, Triple-A teams are using the big league ball. As you’d expect, the home run rates from Double-A on down look very similar to how they did last year. As you’d also expect, the Triple-A home run rate has exploded:

Much has been written about the ball this year: why it’s different, how different it is, how it’s playing in Triple-A, how the league is addressing the controversy, whether or not this is any good for the sport. There seems to be a gap in there though: How are teams themselves responding to the upheaval generated by the ball?

In some sense, the response has been relatively muted. As the year has gone on, we’ve seen individual players like Justin Verlander and retired pitcher Brandon McCarthy express frustration. Other pitchers have clearly noticed, and some of them have been snarky on Twitter, but hurlers have by and large gritted their teeth and kept their heads down.

Similarly, if any teams have expressed concern to the league, they’ve done so very quietly. There’s no outward evidence of any support or derision toward the ball, and front offices have appeared mostly to have noticed and tried to adjust on the fly. In one early-season conversation with a baseball operations analyst, I asked if he or anyone with the team was doing any testing on the ball; he said no, and that he was just waiting for the next Rob Arthur article like everybody else.

In part, that may be because the ball hasn’t redirected the game’s trajectory much. Generally speaking, the trends exacerbated by the 2019 ball — more homers, fewer stolen base attempts, and so on — are just an extension of where the game was already heading. While this year’s ball is extreme, we’ve seen several alterations to the ball’s drag since 2015, most of which have boosted home run totals. Additionally, teams have been trying to get their personnel to hit more balls in the air for years now. The new ball may reward that approach more now than in previous seasons, but it hasn’t significantly altered how hitters go about their work.

More interesting is how teams are coping at the Triple-A level, where we’re seeing a much more dramatic change in gameplay. Jeff Manto, Baltimore’s Coordinator of Minor League Hitting, has noticed that batters are responding to the obvious incentives right now: “The hitters know what’s going on. They all see the ball flying and they want to be part of it. The approach right now is to let it fly.”

That’s resulted in a lot of very similar looking swings. “It’s hard to get guys to be pure mechanical hitters right now,” says Manto. “It’s a high risk, high reward swing, and guys are going for it. There’s certainly no more two-strike swing anymore.” For Manto, his concern is not so much that hitters are trying to put the ball in the air more often. Rather, it’s that the swing equips hitters to only do one thing — and future ball adjustments may leave them unprepared for a more normal home run environment. “The ability to hit every type of pitch and pitcher, that’s what makes a great hitter. At some point the ball’s going to come back to normal.”

In one sense, the ball has actually been helpful for teams. One executive I spoke with said it’s now easier to project a player’s raw power. “You would see players get called up from the minors and show much more power in the major leagues,” he said. “Batting practice is (one) way to evaluate a player’s raw power and I would have to mentally add 10-15 feet to a ball’s distance prior to the switch to the major league ball.”

One surprise was that pushback on the ball was basically a partisan issue. “I’m a pitching coach so you can imagine how I feel about today’s baseball,” said one minor league coach who preferred not to elaborate from there. While most of those I spoke with guessed that the ball would eventually return to a more traditional flight pattern, the hitters didn’t seem to be in any hurry: “You know, as a hitter, I love seeing the ball fly out of the ballpark,” said Manto, who played nine years in the big leagues as an infielder.

Clubs are also responding by handling Triple-A a bit differently as a developmental level. Some organizations already make limited use of Triple-A as a proving ground, preferring to use that team as a taxi squad for the big league club and a home for quad-A type prospects. But a few teams seem to be leery of letting their struggling pitchers take too many lumps.

This is especially significant for teams with affiliates in the Pacific Coast League, where half the circuit either plays at altitude, in a bandbox, or both. The Mariners, for example, sent struggling starters Justus Sheffield and Nabil Crismatt back to Double-A instead of letting them get whacked around in Tacoma, and have promoted a couple of pitchers directly from Arkansas to the big league club this season. The Nationals also regularly shuttle arms from Double-A to the majors, though the logistical hurdles of having their Triple-A team 3,000 miles away in Fresno has influenced that pattern as well.

Still, you can expect this trend to accelerate in future seasons. A National League analyst said that he expects any major shifts in how teams use their Triple-A affiliates to become more apparent next season. “This year, guys got their assignments before we knew something was different with the ball,” he explained. “It’s hard to send a guy back to Double-A just for that, but next year, you might see more arms jump from Double-A to the majors.”

For this analyst, the ball has made it tougher to evaluate the level. “You get guys where there are no major changes in their peripherals, and they’re doubling their home run totals. How do you evaluate that?”

Others just wanted a bit more predictability. “The biggest thing I would prefer would be to avoid large fluctuations in changes to how the ball acts,” said an American League executive who preferred to speak off the record. He also wanted to see more transparency going forward: “If changes are going to be made, make the public aware of any changes of time. So if we go down the route of ‘deadening’ the ball at some point, give teams and the public knowledge of that well in advance.”

Of course, predictability doesn’t mean a return to the past. Asked about what kind of ball he’d like to see in play, the aforementioned executive was sanguine: “I don’t have a major preference. I don’t mind the three true outcomes type shift. I personally think strikeouts and homers are some of the most entertaining plays in baseball.”

Whatever everyone’s opinion on the new ball, a few things are clear: it’s a topic of discussion, and it is changing how analysts and executives operate. It’s also not a discussion that’s losing momentum. As I was wrapping up this article, I got a text from a source I had spoken with earlier in the day:

“We’re literally talking about the difficulties evaluating Triple-A hitters right now.”

Spend any time in a big-league ballpark in the hours before first pitch, and you’ll likely see a pitcher standing in short right or left field, throwing a flat ground. He’ll start his delivery just inside the foul line, feet planted on green grass. His catcher will be around 45 or 50 feet away, half-crouched in the shallow part of the outfield usually reserved for soft line drives. The pitcher will wind and deliver eight or nine times, usually at something like 80% effort, before huddling with his catcher and perhaps a coach or two. Then, gloves loose in their hands, the men will walk back to the dugout to continue their pregame routines.

That scene plays out hundreds of times a day in ballparks across the country. But the practice of throwing flat grounds has come under scrutiny recently, as coaches and front office personnel increasingly worry about the risk of an injury. Over the last few months, I asked a dozen or so players, coaches, and executives about flat grounds and how they’re used. After those conversations, I’m confident in two things: One, most teams who’ve thought hard about the practice have concluded that it has a neutral effect at best and could potentially be harmful. And two, that flat grounds probably aren’t going away anytime soon.

First, the case for flat grounds. For the most part, pitchers I asked told me that they just want to get a better sense of how individual pitches feel coming out of their hands. For that, they insisted, it doesn’t matter whether you’re throwing off a mound or on the field, and faced with the choice between schlepping out to a bullpen mound or simply stepping from the dugout into short right or left field, they prefer the latter. Many discounted immediately my theory that the lack of a drop-down from the mound interrupts upper-half timing based on the moment the front foot hits the ground. “I’ve been throwing flat grounds all my life,” said Marco Gonzales, “and I’ve never noticed a difference.”

But a number of coaches I spoke to expressed variations of the same concern: That practicing pitches on flat ground when they will eventually need to be thrown off a mound gives players bad information about what their repertoire will actually look like in-game.

“We’ve found that the feel guys get for the plate isn’t accurate [while throwing flat grounds],” said the Mariners’ Brian DeLunas. “For sliders and split-fingers especially, you’re just not going to get the same break. I have guys out there who’ll try to throw those pitches, and they’ll be like, damn, this pitch isn’t working! But if your slider isn’t breaking on a 50-foot throw, that’s actually good, because it really should be breaking in the last 15 or so feet.”

There are also elements of standard pitching deliveries that have in-game consequences but simply can’t be practiced on flat ground. “With a flat ground,” said Carl Willis, the Indians’ pitching coach, “the risk is that because you’re not able to get as much extension [on the front half], the consistency of work can suffer. Sometimes you’ll see a guy lose his posture as he comes down the slope, and you want to be able to maintain that posture throughout games. The only way you can really know it, and feel it, is to practice it on the mound.”

But the argument for flat grounds has never been that they replicate an in-game environment. The case is that they’re convenient, and require substantially less effort — and therefore presumably create less wear-and-tear for tired arms — than throwing full-speed off a mound. But is that last claim actually true?

In 2017, Driveline Baseball released a study (building off of a 2014 article in the American Journal of Sports Medicine) that suggested that, holding velocity constant, flat ground pitching generates about 6% more stress on elbows and shoulders than throwing off the mound. Critically, the study also found that stress does not decrease linearly with reduced effort, which means that if pitchers are throwing at 80-90% velocity on flat ground, the stress on their arms is likely about the same as it would be throwing full speed off the mound. Internal studies reaching similar conclusions have led the Mariners, at least, to try eliminating the practice altogether throughout their system (though with limited effect). Other teams have not gone quite as far, despite acknowledging the public evidence.

“If you’re talking about these guys throwing high-effort, it’s a proven fact that flat grounds can be more harmful at the same rate of speed than on the mound,” said Oakland’s pitching coach Scott Emerson. “But if you slow it down, it’s ok. They mostly just use it for target practice. And I’m just using it to see how the pitches look coming out of their hands. Nothing more than that.”

“In my experience, the flat ground can take a little bit of stress off of the arm for guys who are trying to recover,” said Willis. “That’s simply because they’re not working down the slope. That foot plant [which comes 4-6 inches above where it would off the mound] does hinder some extension a little bit, but if you can maintain that delivery, sometimes it tends to help with the recovery, coming back to make your next start.”

To my ear, the persistence of the practice league-wide in the face of reasonably sound evidence that its main theoretical benefit (the lower effort required) isn’t actually a benefit at all seems less about arm stress than convenience.

Most big-league teams carry 12-13 pitchers, and most big-league parks are equipped with just five outdoor mounds: two in the bullpen for each team, and one in the center of the diamond. If teams insisted that their pitchers throw exclusively off of mounds, they’d still only have two mounds to use (the mound on the field being, of course, in use for batting practice, and the remaining four divided between two teams). That would add an element of coordination to a pre-game period already rife with competing priorities for players’ time. “Besides,” one coach told me, “most of our players just aren’t going to walk their asses the 150 yards from the dugout to the bullpen to do their work.”

There’s also a degree of inertia: flat grounds persist because they’re something players have always done. This starts in amateur leagues, where the imbalance between mounds available and players using them is even more stark than in the pros, and where there is even less knowledge of the potentially harmful effects. Gonzales’s response to my question, quoted above, was typical of player responses for this story. Most reacted to my questions about flat grounds as if I had asked them if they put their pants on one leg at a time in the morning, or why they eat breakfast before lunch; they just do, and don’t think much about it. “I’d love it if we had six or seven mounds so we could do all our work there,” said Emerson. “But we don’t. For a lot of our guys this is just a part of their daily routines.”

But as conservative as baseball can be about its traditions and routines, the last two decades of constant self-evaluation and reinvention by coaches and front offices demonstrates that even long-held practices can change when they’re no longer deemed useful. “I don’t think that clubs have really thought hard enough about the risks to flat grounds,” said Bobby Evans, the former Giants’ general manager. “I think the assumption is that it’s just a warmup, when it might really be something that can put players at risk of injury. I want to know more.”

I do, too. There’s a benefit to allowing players to continue long-established routines, to be sure, and it’s probably one I underrate as an external observer of the game. But the evidence for flat grounds as a practice seems flimsy, and I’m not sure I’d be all that invested in it even if the evidence were good. At the very least, I’d welcome the opportunity to learn more about its biomechanical effects. For now, I’m with DeLunas: “Can you imagine a golfer going to the range and spending their afternoon hitting the ball with the back of the club over and over? They would never, ever do that. So why do we?”

The wonderful David Laurila contributed reporting by interviewing Cleveland’s Carl Willis.

Getting traded has long been a part of the game. Players move from team to team on the whims and wishes of general managers looking to make their clubs better — be it in the near term, for a pennant push, or down the road. Sometimes these deals happen during the winter months. Other times they happen in-season, most commonly at the July trade deadline. Either way — and regardless of whether the player is happy with the change of address — more than the name on the front of uniform is going to be different. To varying degrees, getting dealt impacts the day-to-day lives of players, particularly those who have families.

With this year’s deadline fast approaching, I went in search of interesting trade stories. With a broader perspective in mind, I talked not only to current players, but also to former players, a coach who managed in the minors for nine seasons, and a couple of broadcasters. All of these conversations took place last week when the Red Sox hosted the Blue Jays at Fenway Park.

———

Trent Thornton, Blue Jays pitcher

On November 17, 2018, the Houston Astros traded Thornton to the Toronto Blue Jays in exchange for Aledmys Diaz.

“I got a call from one of the front office guys with the Astros, Armando Velasco. I’d just gotten back from the [Arizona] Fall League, so I thought they were putting me on the 40-man roster. Instead, it was, ‘Hey, you were just traded to the Toronto Blue Jays.’ I almost blacked out. I kind of just said, ‘OK, thanks,’ then went in to tell my parents.

“I ended up calling [Valasco] back about five minutes later, because I hadn’t really heard anything he’d said. He was like, ‘Yeah, someone from the Blue Jays will be calling you in about 15 minutes. He’ll give you a little rundown of what’s going on.’

“About 15 minutes later, someone does call. I’m having this conversation with the guy and he’s saying, ‘We’re super excited to have you,’ blah blah blah. At the end of the conversation, I said, ‘Who are you again?’ I’d never caught his name. He goes, ‘Ross Atkins.’ I go, ‘Oh, OK.’ Then I hung up the phone. Read the rest of this entry »

The Boston Red Sox and the Baltimore Orioles completed a trade over the weekend, with Baltimore sending pitcher Andrew Cashner to Boston in return for center fielder Elio Prado and third baseman Noelberth Romero.

At 28-65, the Orioles appear likely to be eliminated from the playoff race sometime in August. Andrew Cashner is a free agent at the end of the season, and even if Baltimore had a less implausible shot at the playoffs, it makes a lot of sense to get something in return for the right-hander while the getting is good. In this case, the getting is two very deep dives into the Red Sox organization. Prado and Romero are both 17 year-olds out of Venezuela. Neither player is anywhere near the top of the prospect radar at this point. To grab a couple of lottery picks, the Orioles agreed to pay half of Cashner’s salary to the Red Sox, a figure just a bit under $2 million. If either prospect works out, it won’t be a new experience for Cashner, who has been swapped for Anthony Rizzo and Luis Castillo in previous trades.

Cashner has had a decent season on paper, but the Orioles’ return suggests that there is a good deal of skepticism surrounding his 3.83 ERA and 4.25 FIP. The bump in Cashner’s peripherals in 2019 is at least enough for ZiPS to think of him as a one-win player. That’s par for the course for a fifth starter, and it just so happens that’s exactly what the Red Sox were in the market for. It isn’t something that will show up well in playoff projections, but remember that teams can no longer pick up major league-caliber fourth and fifth starter types in August, which means that teams ought to take more care to prepare for emergencies now. And pitchers famously have lots of emergencies. Brian Johnson is currently out due to an intestinal issue, and given that he’s been out for weeks, it seems to be something a good bit more serious than overindulging in spicy chili. He has thrown a couple of bullpens, but his trip to the IL creates some uncertainty, which isn’t a good state of being for a contending team. And Cashner is likely a safer below-average pitcher than Hector Velazquez. Read the rest of this entry »

Jim Bouton first made his mark as a star right-hander for the Yankees at the tail end of their 45-year dynasty, winning 39 games in the 1963-64 regular seasons (plus two more in a pair of World Series), and making one All-Star team (’63). Yet his second act — after he injured his arm, lost his fastball, and hung on to his career literally by his fingernails, trying to tame the knuckleball with the expansion Seattle Pilots — was far more interesting and impactful. Bouton began keeping notes chronicling his travails, which, with the help of editor (and fellow iconoclast) Leonard Shecter, became Ball Four. His candid, irreverent, and poignant “tell-some” account of his 1969 season with the Pilots, Triple-A Vancouver Mounties, and Houston Astros not only became a best seller, it revolutionized the coverage of athletes, and keyed a proliferation of inside-baseball books that went far beyond the diamond. Recognized in 1996 as the only sports book among the 159 titles selected for the New York Public Library Books of the Century, Ball Four brought Bouton enough fame and notoriety to last a lifetime. That lifetime ended on Wednesday, when Bouton, who was 80 years old and suffering from vascular dementia, passed away at his home in Great Barrington, Massachusetts.

With its candid glimpse into the lives of major league ballplayers — hard-drinking, skirt-chasing, amphetamine-popping athletes using four-letter words — as they attempted to cope with the pressures and the boredom of the game, Ball Four was raunchy and controversial. Set against a backdrop of social upheaval, the outsider Bouton often found himself at odds with his teammates regarding the war in Vietnam, race relations, politics, and the burgeoning union movement within the game, which would eventually challenge the Reserve Clause, leading to higher salaries and the right to free agency.

Amazingly, such an explosive exposé did not win Bouton many friends within baseball. Fellow players accused him of violating the sacred trust of the locker room. His ex-Yankees teammates were said to take it very hard, particularly Mickey Mantle, whose debauchery had previously been hidden from fans by writers who had sanitized heroes for public consumption. Bouton, whose major league career ended shortly after the book was published in 1970 (though he made a brief comeback with the Braves in 1978), was effectively blacklisted by the Yankees until 1998, after the tragic death of his daughter Laurie in an automobile accident prompted his son Michael to write an open letter to the New York Times, asking the team to help Bouton heal old wounds by inviting him to Old-Timers’ Day. They did, and Bouton was greeted with a warm ovation. His cap flew off on his first pitch, a signature from his playing days.

When excerpts of Ball Four first appeared in Look Magazine in the spring of 1970, MLB commissioner Bowie Kuhn tried to get Bouton to recant his claims and state that the book was fiction. “It was the perfect form of censorship,” the pitcher-turned-author recalled in 2010, on the occasion of the book’s 40th anniversary. “The publisher had only printed 5,000 copies on the grounds that nobody would want to read a book about the Seattle Pilots written by a washed-up knuckleball pitcher. Then the baseball Commissioner calls me in, and they have to print another 5,000 and then 50,000 and then 500,000 books…” Including 10th, 20th, and 30th anniversary editions with epilogues that created what MLB’s official historian John Thorn called “a candid, sometimes heartbreaking extended memoir without parallel in American literature,” Ball Four sold millions of copies worldwide. Read the rest of this entry »

Last week, I saw Dodgers lefty Clayton Kershaw in person for the first time. While he’s no longer the dominant force of nature he was at his peak — Kershaw’s fastball now sits 89-91, rather than sitting 92-94 and touching 97 as it did 2015-2017 — he’s still a very effective big league starter, on pace for a 4 WAR season, and the owner of a 3.51 xFIP across just under 100 innings pitched ahead of the All-Star break.

This is far from the first piece on this website to chronicle what makes Kershaw great as, over the last decade, he’s improved his command, and altered his pitch mix and pitching approach. What I suggest today is that part of his continued success also has to do with, simply, how he releases the baseball, and that this trait is identifiable in prospects.

It’s probably obvious to you that things beyond mere raw velocity contribute to fastball effectiveness. You can probably deduce what some of those things are through simple pattern recognition; the System Summary from this prospect list is an example of that. From having done this for a while now, there are common, visually identifiable characteristics shared by pitchers whose strikeout results outperform what we might anticipate given just their velocity, just as there are common mechanical/stuff-related attributes targeted by successful teams in the draft. (Those teams have also made mechanical and/or approach alterations to players they’ve acquired.) Spin rate, extension, vertical and horizontal approach angles, and spin direction/efficiency all play a role, too, as does command.

The more those traits serve to support vertical movement — a.k.a ‘rise’, life, carry, Z-break — the more swings and misses a fastball tends to generate. And when a fastball exhibits several of these traits, you can end up with a dominant heater despite limited velocity. Without them, I’ve been bamboozled by otherwise visually pleasing stuff. And indeed Clayton Kershaw’s fastball has some of these attributes. At 88-91, his fastball is still fine. In the mid-90s, it was utterly dominant.

The way we talk about these traits in scouting and player development is not yet entirely consistent across baseball. I was on the phone with an in-office analyst last week discussing what would eventually become this article, and we were using the same terms to describe different things, which caused us to argue for about 10 minutes before we realized we were simply miscommunicating. This video and these two articles provide a great foundation for understanding how pitches need to spin in order to create vertical movement. The version that has been most intuitive for me is the Rapsodo/TrackMan version, which describes spin direction by using a clock face from the pitcher’s perspective. The closer fastball tilt gets to 12:00, the more backspin it has. For the purposes of this article, I’m just looking at lefties, but you’ll be interested to know that some frequently-asked-about prospects like Zac Gallen (12:30 spin axis on the fastball), Astros RHP Jose Urquidy (91-95, up to 97, plus changeup and command, smart breaking ball usage, a 12:30 spin axis on the heater), and Ashton Goudeau (90-93, also has 12:30 spin axis, plus split/change) have some of the traits I’ve talked about.

It’s fair to watch a pitcher’s arm angle and assume that vertical arm slots create the kind of backspin we’re looking for, but we can better see the ball/hand relationship, including sub-optimal ones, using our high-speed camera, Slomie. If you didn’t read the Driveline and Laurila background articles, we’re looking for something close to pure backspin and seam uniformity. You’ll be unsurprised to see Clayton Kershaw exhibit both. At peak, he was averaging over 12 inches of Z-break on his fastball. He’s closer to 10 inches now, which is still above league average:

Spin rate is a factor here, too, and we have those for most of the minors. So based on information we have, here some lefty pitching prospects who I think also exhibit some of these Kershawian traits. I don’t anticipate any of them becoming as incredible as Kershaw, but they do possess mechanical characteristics that will enable them to get the most out of their stuff. Full scouting reports for most of these players can be found on THE BOARD.

MacKenzie Gore, San Diego Padres
Gore has all the components: the velocity, the spin axis, the seam uniformity, elite athleticism, some natural mechanical deception. He doesn’t spin his curveball as well as Kershaw, but his changeup is better. He’ll be in Sunday’s Futures Game.

Joey Wentz, Atlanta Braves
Wentz doesn’t have the quality breaking ball but his fastball plays well above it’s 88-91, and he has good changeup feel.

Ethan Small, Milwaukee Brewers
The Brewers 2019 first rounder is Kershaw’s mechanical doppelgänger. In 2019, he struck out 176 hitters in 107 innings for Mississippi State, most of them in the SEC, while sitting 88-92.

Joey Cantillo, San Diego Padres
Cantillo, a 2017 16th rounder out of a Hawaii high school, only sits about 88-92, but the life on his fastball and the quality of his secondary stuff has him missing lots of bats in the Midwest League. He hasn’t allowed more than one run in a start since April 26.

Tarik Skubal, Detroit Tigers
Skubal’s full report is on The Board. He ranks 14th in the minors in swinging strike rate.

Erik Miller, Philadelphia Phillies
He doesn’t get into his legs the way Kershaw does, and the velocity fluctuations Miller has experienced over the last year and a half is a bit concerning, but he has the pitch specifications I’ve outlined above and knows how to mix his stuff.

Burl Carraway, Dallas Baptist University
I anticipate Kiley will have high speed of Carraway in the coming days, as he’s been electric for Team USA recently, up to at least 97 with a knockout breaking ball.

Drew Dowd, Junipero Serra HS (CA) and Ross Dunn, Cottonwood HS (UT)
These were the two high schoolers at PG National whose fastballs I thought played up above their velocity for the reasons I’ve outlined above, though Dowd might be better off working with a four-seamer.

The lingering suspense over whether the Yankees could break the major league record for consecutive games with a home run, which they had tied at 27 on Monday night, lasted until Tuesday night’s sixth pitch from Blue Jays starter Clayton Richard to Yankees leadoff hitter DJ LeMahieu. Boom!

In the brief interval that it took this scribe to tweet about that record — admittedly, while juggling a beer and a scorebook in section 422 of Yankee Stadium — Aaron Judge homered as well. In fact, solo home runs accounted for the Yankees’ entire output in their 4-3 victory, with Gleyber Torres and Edwin Encarnacion joining the party, too. The latter even broke out the parrot against his old team for just the second time since departing in the winter of 2016-17, that while a hawk literally watched his dinger from atop the right field foul pole.

Here’s the Yankees’ new perch after Wednesday, when Didi Gregorius’ second-inning home run off Toronto’s Trent Thornton further extended the streak (LeMahieu added another one in the Yankees’ come-from-behind win as well):

It doesn’t take the eyesight of a hawk to note that 11 of those 13 seasons are from the post-1992 expansion era, which has featured at least one home run per team per game — a level previously topped only in 1987 — in all but five seasons (1993, and every year from 2010-14 except for ’12). Four of those seasons, including three of the top seven, are from the 2016-19 period, which, as I noted on Monday in relation to Justin Verlander’s performance, is the first four-year stretch with at least 1.1 home runs per team per game. This year’s 1.36 per game is the all-time high, 0.1 ahead of the previous high set just two seasons ago, an increase of 8.7%. It’s 0.21 home runs per game (18.8%) higher than last year, and 0.5 homers per game (58.4% higher) than in 2014, the year of the post-1992 low:

If we factor in the ever-increasing strikeout rates, the rise is even sharper. This year’s rate of home runs per batted ball — that is, HR/(AB-SO+SF) — is 5.31%, 0.49 points (10.1%) higher than the previous high in 2017, 0.86 points (19.3%) higher than last year, and 2.08 points (64.2%) higher than 2014.

I’ll get back to that momentarily, but it’s worth noting that when the Yankees’ streak began in late May, only three of the seven players who contributed the most home runs to last year’s record-setting total of 267 were active, namely Aaron Hicks (who tied for second on the team with 27 homers), the sixth-ranked Torres (24), and seventh-ranked Gary Sanchez (18). Since then, the 1-2 punch of Giancarlo Stanton (38) and Judge (27) has returned from lengthy stints on the injured list, and Gregorius (27) has returned from off-season Tommy John surgery. Miguel Andujar (27) is out for the remainder of the season due to surgery to repair a torn labrum, but on June 16, the team traded for Encarnacion, who currently leads the league in homers (24, including three as a Yankee).

All of which is to say that it’s been a mix of A- and B-list players who have not only propelled this particular Yankee streak but have helped the team out-homer all but three other teams, namely the Twins (149), Mariners (145), and Brewers (138):

Such are the Yankees’ power reserves that the acquisition of Encarnacion led to Frazier, who has hit a robust .283/.330/.513 (117 wRC+), being optioned to Triple-A Scranton/Wilkes-Barre, and remaining on the farm even as Stanton went back to the IL with a sprained posterior cruciate ligament in his right knee, the result of a baserunning mishap early in Tuesday night’s game. He’ll miss the upcoming London series against the Red Sox, and will be out for longer than the 10-day minimum. With or without Stanton, who has played just nine games this season, it’s not hard to imagine a more complete Yankees lineup overtaking the Twins in the home run department. But even if they don’t, the rather patchwork lineup has kept them on pace to eclipse last year’s total, which is a hint that the homer situation is simply getting silly.

League-wide, no individual is on pace to challenge Barry Bonds‘ single-season home run record of 73; Christian Yelich, who leads the majors with 29 homers, would finish with 62 if he were to keep hitting them at the same pace over the Brewers’ final 82 games as he has over his first 73 (he’s missed seven games with assorted aches and pains). However, with only five teams past the halfway point in their schedules heading into Thursday (the Mariners have played 84 games, the other four of those teams 82), a total of 56 players had reached the 15 homer plateau, meaning that they were on pace for 30 homers. The league-wide record for such players is 47, set in 2000. Four of the top five totals hail from the 1996-2001 stretch, with the fifth coming in 2017, when 41 players reached it. Similarly, 18 players have reached 20 homers, and are on pace for at least 40. The record for players with 40-homer seasons is 17, set in 1996, and we haven’t seen more than nine players do it in any Statcast-era season; there were nine in 2015, but just three last year. Yelich, Pete Alonso (27 homers through the Mets’ 81 games) and Cody Bellinger (26 homers through the Dodgers’ 82 games, including one on Wednesday) are on pace for at least 50 homers. Only in 1998 and 2001 did more than two players reach that plateau, with four apiece in both of those years, including the single-season record breakers, Mark McGwire and Barry Bonds.

Meanwhile, 14 of the majors’ 30 teams are on pace to set franchise records, with the top four surpassing last year’s Yankees:

All but three of the 30 teams are averaging at least one homer per game. Twenty-two teams are on pace for 200 homers, one fewer than in all of baseball prior to the 1994 players’ strike. Only in 2017, when 17 teams reached that plateau, have there even been as many as a dozen teams to do so. Eight teams are on pace for 250 homers, a level reached by just six teams ever prior to this year. The mind reels at these numbers.

While one can point to the general trend of batters making greater efforts to elevate the ball — whether to hit it over shifted infielders or not — it’s more accurate to call that an adaptation to the new reality. The scientific evidence again points to the ball itself as being the driving factor. Earlier this week at The Athletic, Dr. Meredith Wills published a follow-up to last year’s breakthrough article, which itself was a follow-up to MLB’s Home Run Committee report. That committee, led by Dr. Alan Nathan, professor emeritus of physics at the University of Illinois, had found that the recent home run spike was caused by a decrease in the ball’s aerodynamic drag, but found no physical difference in the balls that would explain the change.

Conducting her own measurements using digital calipers and disassembled baseballs, Wills concluded that post-2015 balls’ laces, which were an average of nine percent thicker than balls from the 2010-14 period, were producing less bulging at the seams, yielding a more spherically symmetric ball with less aerodynamic drag — thus allowing them to fly further.

For her latest study, Wills examined 39 balls from this season, which she found differed from the 2015-18 balls and even earlier ones. Most notably, she found “demonstrably lower” seams, only 54.6 percent ± 15.0 percent as high as those on balls from previous seasons. By measuring the coefficient of static friction, she also found that the leather on this year’s balls is relatively smoother, concluding, “the static friction for the 2019 balls is 27.6 percent lower, a statistically significant result demonstrating the leather covers are genuinely smoother.” She measured the bulging of the seams and found, “Not only were the 2019 balls virtually round, what bulging they did show was slightly negative, suggesting the seams might be slightly ‘nestled’ into the leather.” The significantly rounder balls, which have thinner laces than last year’s (more in line with 2000-14 samples) produce even less drag than before, and thus even more carry. Wills noted that both the seam and smoothness issues jibe with anecdotal reports from pitchers about difficulties in gripping this year’s balls, as voiced by players such as Sean Doolittle, Jon Lester, and Noah Syndergaard.

As for commissioner Rob Manfred’s recent suggestion that a better-centered pill (the core of the ball) is a factor in creating less drag, Wills was largely dismissive, writing, “[T]his is the most difficult result to produce without significant manufacturing changes, since existing techniques make it hard to keep the pill from being centered to begin with… Therefore, it seems unlikely that pill-centering would explain a sudden change in drag; at the very least, we would be remiss not to also examine other possible sources.”

All of Wills’ articles on the topic, which are behind a paywall, are worth reading, but it should suffice to say that there’s ample scientific evidence that the ball is carrying this. And how. Check out these numbers, which combine Statcast’s average distance measurements with those from our stat pages:

Fly balls are carrying an average of four feet further than last year, and eight feet further than in 2015. Add to that a general increase in fly ball rates and you have a recipe for significantly more homers. Perhaps too many homers. Combine that trend with the aforementioned strikeout trend and lower batting averages — though this year’s .251 is three points higher than last year, it’s in a virtual tie with 2014 for the second-lowest mark of the DH era, which began in 1973 — and the result is a greater percentage of runs being scored via homer than ever before. Here’s an historic look at what Joe Sheehan christened “the Guillen Number” a decade ago at Baseball Prospectus:

For a period of over two decades, from 1994-2014 — two decades that saw record home run rates, PED scandals, expansion, new ballparks galore — the rate of runs scored via homers was remarkably stable around 35%, never deviating more than two points in either direction. It hit 37.3% in 2015, and has climbed at a rate of about two points per year since, to heights previously unseen, and now, both statistically and aesthetically, the situation sticks out like a sore thumb. Ken Rosenthal called it “Bludgeon Ball” earlier this month, and I think the description fits. This is brute force baseball, and while it doesn’t lack for a certain amount of excitement, it’s very lacking in subtlety. When nearly half the league is on pace to set home run records, and the vast majority of teams are set to exceed totals that were once very rare, we’ve gone too far.

It’s time for MLB and Rawlings (which the league bought last year) to fix this. Wills noted that while Manfred has maintained that Rawlings hasn’t changed its manufacturing process or materials “in any meaningful way,” this may be an issue of semantics:

The Home Run Committee found that Rawlings regularly implements production improvements, including changes to the yarn (February 2014), the pill (March 2014, May 2015), the leather (June 2014, February 2017, August 2017) and the drying process (March 2016, February 2018). The Committee described these changes as “largely technical in nature and very unlikely to be in any way related to the (2017) home run increase.” That being the case, things like enhancing leather smoothness or drying baseballs more efficiently might not be considered “meaningful” to manufacturing.

While this may have been a reasonable attitude in the past, such enhancements now appear to have compounded, producing a more aerodynamic ball.

Wills recommended another committee report with the goal of using the information to tighten specifications, improve quality control and “determine further production improvements.” To these eyes — and I know I’m not alone — such improvement would include the restoration of some normalcy. When a player’s 40-homer season, or a team’s mountain of 200 homers, is no longer worthy of celebration, is as common as a garden weed, we’ve lost something. It’s worth searching for how to get that special something back.