One major point of contention in this offseason’s collective bargaining impasse is compensation for young players. In the two sides’ competing proposals, the existing Super Two system, which each year awards an additional year of arbitration to some pre-arb players with two-plus years of service time, has come up repeatedly. Whether it’s being replaced with an algorithmic solution, increased pay for some players based on performance, or an expansion of arbitration within the two-plus group, compensating these pre-arb but multi-year players is a key point of debate as the lockout wears on.

If we want to understand this debate, we need to understand how Super Two players have been compensated in the existing system. Without that context, the dispute can feel more theoretical than consequential, and it is obviously very consequential to the players involved. To that end, I decided to look at the last eight years of Super Two awards and come up with a rough heuristic for how their compensation relates to their production in those years. From there, I’ve created some rules of thumb, which I’ll share with you here before we get into the nitty-gritty details of how I did the calculations. Here it is, separated out by player type:

This table displays the amount of money a given player should make above the major league minimum based on how many times they’ve been through the arbitration process, their position, and their previous year’s production. Broadly speaking, the numbers make sense — players receive less per unit of production than they would in free agency, but their compensation gets closer and closer to free agency levels (roughly $6.5 million above minimum salary per WAR) as they go further into arbitration. Now let’s talk about how I got to these numbers, and the merits (and limits) of using this style of calculation to model arbitration awards. Read the rest of this entry »

This time last year, I investigated where vertical approach angle (VAA) seems to matter most. The short answer: at the top of the strike zone for four-seam fastballs and at the bottom of the zone for sinkers and two-seam fastballs. This piece, which is adapted from a presentation I did as part of the 2022 PitcherList PitchCon, will provide much-needed additional context, like benchmarking and watermelon-colored heat-map-style graphics.

For the uninitiated — which could be many of you — VAA is the angle at which a pitch approaches home plate… vertically. Despite its usefulness, the concept has experienced slow uptake in the public sphere. I think that’s largely due to a lack of data, which, for nerds like me too entrenched in baseball Twitter, has shrouded the metric in mystery. Why are scouts and college baseball R&D departments valuing VAA so highly, why have I barely heard of it, and how can I find it?

To answer the last question: Statcast is granular enough that, fortunately, we can calculate VAA using physics. So, let’s calculate it! Thanks to Baseball Prospectus‘ Harry Pavlidis (who credits baseball’s renowned physicists), here are the equations: Read the rest of this entry »

If you wanted to design a puzzle to attract my interest, you couldn’t do much better than pitchers who throw both sinkers and four-seamers. I love thinking about pitching. I love thinking about fastball spin, and I’ve been having a blast looking at approach angle recently. Want to kick it into overdrive, though? Add in platoon splits, and we’re really cooking with gas.

One of those weird, of-course-this-exists-but-we-don’t-talk-about-it splits is groundball pitchers against flyball hitters and vice versa. I first learned about this split in The Book, and while it’s always made sense, Alex Chamberlain put it into a pretty picture recently that brought it back to mind for me:

fly ball hitters perform better against ground ball pitchers, and ground ball hitters perform better against fly ball pitchers

(y-axis: pitcher influence on launch angle
x-axis: hitter LA, absent pitcher influence
colors: hitter wOBAcon bins) pic.twitter.com/K43Kj868T5

— Alex "Oxlade" Chamberlain (@DolphHauldhagen) January 21, 2022

There are some terms you might not know on there, like pitcher influence on launch angle. For that, you should read Alex’s work on launch angle here. Honestly, you should probably just read all of Alex’s stuff anyway – but particularly for this, his work is invaluable.

The key takeaway here? Against groundball hitters, sinkers are an excellent choice of pitch. The hitter tends to hit the ball into the ground and sinkers generally influence launch angles downward. The result is frequently a grounder, which is great for the defense. Similarly, if you’re facing a fly ball hitter, you want them to hit it even higher into the air, which means a four-seamer with solid rise is the ticket. Read the rest of this entry »

Is throwing a four-seam fastball down the middle a good idea? Regardless of whom you ask, the answer is probably no, and for good reason – the heart of the zone is where the majority of hard contact occurs, and fastballs are the most contact-prone of any pitch type. This disdain is rooted in our baseball lexicon, too. You’ll notice that after a ball is hit out of the park, broadcasters tend to remark that the pitcher “left one over the middle” or “hung his fastball.” The location is often to blame.

That doesn’t stop pitchers from trying, though. That’s not always because they want to – command comes and goes, after all – but it’s also because hitting a baseball is extremely difficult. Swings and misses happen! Bad contact happens! In each season since 2015, when Statcast data became public, hitters have accumulated a negative run value against down-the-middle fastballs. They’re still in the red despite seeing easier pitches. Though no pitcher would want to live solely in the middle, it makes sense why one might venture there.

But 2021 brought changes to the majors, and this is one of them: Hitters did worse against so-called meatballs than ever before. Here’s a graph that shows the league’s run value per 100 against fastballs in Baseball Savant’s “Heart” zone. Again, 2015 is the starting point:

Read the rest of this entry »

“Just platoon it.” Whenever a team has a weak spot in their lineup, that’s the first thing I think of. Limp left field production? Just sprinkle some platoon on it, and you could be living large. Second base got you down? You’re just one platoon away from competence, or even excellence if you play your cards right. Second base and left field are bad? Bam, platoon them both!

It isn’t actually that easy. If you want to deploy a platoon in the majors (as opposed to in theory, my favorite place to deploy platoons), you have to wrangle with reality, which is notoriously unforgiving. In that vein, this is an article I’m writing to remind myself how hard it is to run multiple platoons at once. It’s not necessarily a reason not to platoon. It’s not even a critique of platooning. It’s just that in my head, and potentially in yours, teams are passing up platoon spots left and right. Here are some reasons why that isn’t true.
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On the surface, popups may seem a bit mundane. Typically, the ball isn’t even visible on the broadcast and they are nearly always converted into outs. Nearly always isn’t always, though, and dropped popups are a treat to behold. And even if you aren’t lucky enough to see one actually drop, plenty of weird things can happen on plays that start off routine:

Since it’s the middle of the offseason, I thought it would be a good time to take a closer look at the popups of 2021. I don’t want just any old popups, though. I want the best of the best — the popups that cause players to lose their feet, the ones that make the crowd “ooh” and “aww” as the ball simply refuses to come down.

The easiest way to find these sky-scraping popups is to base our search off of exit velocity, as balls hit harder will go higher. An exit velocity of at least 97 mph seemed like a good cutoff point. Any lower, and the popups would start to feel less impressive; any higher, and the sample wouldn’t be large enough to satiate my desire to watch this sort of play. That cutoff left me with 126 popups representing the hardest 1.5% of popups hit this season (if you’d like to follow along, you can find the whole batch here on Baseball Savant). Read the rest of this entry »

Back in December, I wrote about Cedric Mullins’ breakout 2021 season, the catalyst for which was a decision to stop switch-hitting and begin batting exclusively from the left side of the plate. By dropping his right-handed swing, Mullins, a natural lefty, could focus on honing one swing instead of struggling to maintain two separate swings.

Switch-hitting has always been a rare skill throughout baseball history, but the number of batters who can swing both ways has dwindled in recent years. From that previous piece:

In 2021, just 17 qualified batters (13.1%) were switch-hitters, right in line with the league-wide average over the last decade. Compare that to the decade between 1986 and ’95 (excluding the strike-shortened 1994 season), when more than one in five qualified batters (21.1%) hit from both sides, with a peak of 24.8% in ’89. With modern baseball strategy so heavily emphasizing the platoon advantage, it’s surprising to see so few switch-hitters these days. Giving up that advantage in every at-bat is a radical decision, and there’s barely any precedent for it.

The number of players who have dropped switch-hitting after making their major league debuts is tiny. J.T. Snow did it in 1999, halfway through his career. So did Orlando Merced in 1996. Shane Victorino flip-flopped between switch-hitting and batting right-handed after injuries forced him to give up left-handed batting at various points during his career. More recently, Tucker Barnhart gave up switch-hitting in 2019.

After seeing the success Mullins had after giving up swinging from the right side, the obvious follow-up question is whether we can identify any other switch-hitters who might benefit from focusing on swinging from one side or the other.

The extremely small number of players who have actually made the decision to stop switch-hitting at the major league level should tell us that this isn’t a silver bullet solution to a player with a wide platoon split. Anecdotally, more players stop switch-hitting in the minors because they have a lot more to gain if the adjustment pays off. For those players who have already made it to the majors but haven’t truly established themselves, like Mullins, it’s a risky decision. They’d be making the change against the best the sport has to offer, likely resulting in a significant adjustment period. Still, with teams focused on finding every miniscule advantage to wring out of their rosters, it’s a worthwhile question to pursue.
Read the rest of this entry »

Writing about baseball isn’t the most predictable task. I often don’t know what my topic will be until the dust settles, hours after rummaging through a pile of numbers that, at first glance, makes little sense. For example, this article started off as an inquiry into Darin Ruf. Of all the journeymen to stop by the KBO, experience a resurgence, and return stateside, he’s by far enjoying the greatest success – who would have guessed?

As a right-handed hitter, Ruf’s primary asset is a knack for mashing lefty pitchers. He can hold his own against righty pitchers, too, posting a 126 wRC+ against them last season. But detractors might point to a .386 BABIP that buoyed much of that production. In other words, one could expect Ruf to become a bit more… rough in the future (sorry). A quick search reveals that he had a higher groundball rate against righties compared to lefties, which doesn’t bode well for future success, and not much else. The critics win this round.

Here’s the thing, though – he wasn’t alone. It turns out that in 2021, right-handed hitters had a higher groundball rate against right-handed pitchers; conversely, they had a lower groundball rate against left-handed pitchers. You can see for yourself:

This is also true of left-handed hitters. Facing same-handed pitchers led to more groundballs, while opposite-handed pitchers led to, well, the opposite. The gap in groundball rate by pitcher handedness is greater for lefty hitters, though that may be influenced by the relatively few instances of lefty-versus-lefty matchups. Still, the difference, which appears on a league-wide scale, is significant enough to warrant an investigation. Read the rest of this entry »

The week before Christmas, I conducted an investigation into the Giants’ strange sinker-ballers. Logan Webb and Alex Wood enjoyed spectacular years, and they both did it using sinkers they released from a low starting point, which created a unique look for batters.

You probably didn’t read that article, and that’s okay. It was the peak of the holiday season. You were likely out in the world like me – seeing family, drinking eggnog-flavored coffee beverages, and generally making up for last year. My consumption of baseball media went way down, and I do this for a living.

As a self-interested person, I suggest you go back and read that article. I thought it was pretty good! More importantly, though, I’ve been doing more research into what the heck a “flat sinker” even is. The concept just doesn’t fit into my brain, and when that happens, I like to hit myself over the head with data until something clicks. So today, please enjoy some random things I’ve researched while trying to understand why in the world “flat” (approach angle) and “sinker” (pitch type) coexist. Read the rest of this entry »

For nearly a decade, you couldn’t go a week in the offseason without seeing an article about the American League’s dominance over the National League in interleague play. I know – I was already a rabid consumer of Hot Online Baseball Takes™ at the time and drove myself to distraction trying to find reasons to believe or disbelieve it. But it was interesting! The AL and NL split World Series roughly down the middle, but the AL kept winning interleague play and World Series games. Was it just a better league?

In 2018 and ’19, the trend flipped. The NL won the interleague season series in both of those years, which marked their first victories in that theoretical season-long series since 2002 and ’03. It had been quite a while, in other words.

By 2020, “who’s winning the interleague series” didn’t feel as interesting, and the unique pandemic-shortened schedule drove that point home even more surely. Due to geographically-divided schedules, there were nearly as many interleague games in 2020 as there were in ’19 (298 league-wide as compared to the standard 300 on the schedule every year since 2013), despite playing a 60-game season rather than 162. Not only that, but there wasn’t the usual rotation of opponents and rivalries. Instead, each division played its opposite-league counterpart. Read the rest of this entry »