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Matthew Boyd Is Walking a Fine Line

Matthew Boyd had a tough 2020 campaign. After posting a 3.3 WAR season in 2019, Boyd’s performance cratered last year. His ERA- increased from 97 to 149 and his FIP- 93 to 128. He lost about eight percentage points on his strikeout rate (30.2% to 22.1%) while adding almost two points to his walk rate (6.4% to 8.1%). Boyd was putting close to 10 more batters per 100 faced on the basepaths year over year and the home run troubles he developed in 2019 did not subside.

Through his first four seasons in the majors, Boyd allowed home runs on 12.4% of his fly balls. That figure jumped to 18.2% in 2019 and 19.7% in ’20. Among qualified pitchers, that was third highest in the league, behind Kyle Gibson and Alec Mills. But where Gibson and Mills both posted above average groundball rates (51.5% and 47.3% respectively), Boyd only induced groundballs on 37.2% of his batted balls against. Not only were Boyd’s fly balls leaving the yard at one of the highest rates in the league, he also gave up a lot of them. All these issues culminated in Boyd allowing a .453 wOBAcon and accumulating just 0.1 WAR in 60.1 innings pitched, far off the pace he set in 2019. The former value was by far the worst in the majors in 2020. Indeed, Boyd’s wOBAcon allowed was almost 20 points worse than his next closest peer.

One of the culprits behind his 2020 demise was the degradation of his slider. The pitch was a consistent source of swings and misses in 2019; Boyd threw the slider 22.7% of the time and generated whiffs on 43.6% of swings. He increased its usage to 28.1% in 2020 but the whiff rate tumbled fell to 39.4% — still an impressive figure but given how often he throws the pitch, that is a lot of lost whiffs. He struck out batters with 52.5% of his two-strike sliders in 2020 after 58.5% in ’19, which can be attributed to more sliders finding the middle of the plate last year. Read the rest of this entry »

Let’s Look At Some Early-Season Plate Approach Changes

It is still early in the season, but one of the aspects of hitting that stabilizes relatively quickly is changes to approach. Swings are a more common occurrence, so the sample for these statistics grows faster than those that rely on an accumulation of plate appearances. So who seems to have made some changes in the early going?

To get an idea, I took all players who accumulated 250 plate appearances combined in the 2019 and ’20 seasons (I chose to group these seasons together because of the brevity of the pandemic-shortened campaign), then filtered by those who meet the qualified criteria in 2021. This leaves a sample of 159 hitters; each table includes the top and bottom ten players for each metric.

Read the rest of this entry »

The Case for Slowing It Down

I would imagine that one of the most jarring pitches for a major league batter to face is an extremely slow breaking pitch. Conventional wisdom might suggest the opposite — something like triple-digit heat. But at least a batter knows to expect high-end velocity when he steps to the plate against a given pitcher. A pitch under 70 mph, on the other hand, is rare enough that it can freeze you. Not familiar with the types of pitches I am talking about? Here are a select few.

Since 2015 (i.e., the Statcast era), just 0.3% of all pitches thrown in MLB have been under 70 mph; pitchers today generally live in velocity bands from 10 to 30 mph higher. Being able to slow the ball down to such an extreme degree without tipping off the batter to what is coming is not trivial, and being able to drop these pitches in for strikes takes practice. Taking time in a throwing session to lob lollipops into the strike zone probably seems foolish to many pitchers, especially if they can just throw 95 mph instead.

I understand the roadblocks to throwing slow looping curveballs. But whenever I see a pitcher throw them, they often seem to disarm the batter, who usually doesn’t swing. In that scenario, the worst-case result is often a ball, and if the pitcher can locate the pitch, he can nab a strike with little resistance. And as fastball velocity continues to increase across the league both this year and in seasons past, pitchers are increasingly leaning on breaking balls and offspeed pitches to fool hitters who are geared up for heat. With that in mind, a super-slow curveball could be a useful weapon. Read the rest of this entry »

Another Post About Fastball Velocity

If you felt like you hadn’t gotten enough fastball velocity analysis at FanGraphs in the past week, do I have a treat for you! Last week, Kevin Goldstein expounded on the importance of the shape of a fastball in determining its effectiveness, making it clear that velocity is the driving factor in evaluating a fastball, but that deviating from a “normal shape” (interpreted as an inch of ride for every inch of run) can lead to missing more barrels. Devan Fink, meanwhile, showed that fastball velocities have increased across the league to start the year, which is especially striking since fastball velocities are usually at their nadir in April. Devan also highlighted pitchers who have seen an especially large bump. Finally, on Friday, Jake Mailhot took a look at Chris Paddack’s first start with a focus on the righty’s fastball after a disappointing 2020 season.

I recommend reading all those pieces, if you haven’t already. Kevin and Jake give credence to the idea that fastball shape is an essential factor in a good fastball. But I want to focus on Devan’s article on fastball velocity and how it seems to be increasing again in 2021, as it has every season since 2008. One can surmise that this is a product of pitchers acknowledging the importance of velocity (thus training with gains in mind) and teams giving more innings to pitchers who, by and large, throw harder. Velocity obviously matters, but how much? Read the rest of this entry »

Tim Anderson’s High-Wire Act

Tim Anderson is a befuddling player. Over the last two-plus seasons, he has posted a 133 wRC+ despite a minuscule walk rate (3.3%) that is the third lowest among all players with at least 500 plate appearances, ahead of only slap hitters José Iglesias and Hanser Alberto. That puts a lot of pressure on his ability to produce on contact. So far, so good: In that same time frame, he has a .390 BABIP, tops among all hitters and a full eight points above the next closest player (coincidently, his teammate, Yoán Moncada). The normal expectation is that a BABIP figure that high is unsustainable, and the projection systems tend to agree. The FanGraphs Depth Charts pegged Anderson for a .336 BABIP in 2021 and, correspondingly, a batting line just three percent better than league average.

If Anderson is going to be a productive hitter, then, one of two things needs to happen: He sustains a BABIP that is not just 100 points above the league average but also one of the best figures of all-time; or he improves in plate appearances that do not end with a ball in play. So how likely is either?

Let’s start with the BABIP. Anderson does not hit the ball especially hard. In the last two seasons, he ranked in the 33rd and 40th percentile, respectively, in hard hit rate, according to Baseball Savant. Last season he almost doubled his barrel rate, going from 5.1% in 2019 (23rd percentile) to a career-high 10.1% (65th), but that 2020 figure constituted all of 16 batted balls. Nor has he shown too much selectivity in his career or discriminated against pitches within or near the strike zone, as you can see in the sea of red below.

Read the rest of this entry »

The Obvious Vladimir Guerrero Jr. Tweak

This is Carmen’s first piece as a FanGraphs contributor. Carmen is an engineer living in the Bay Area. Born and raised in Connecticut, his inherited Yankees fandom (yes, he can hear all of your grumbles) and curiosity about math and science combined to foster a fascination with how players contribute to run scoring and prevention, as did growing up reading the venerable pages of sabermetric havens such as FanGraphs, Baseball Prospectus, and Beyond the Boxscore. The accessibility of pitch-by-pitch Statcast data has allowed him to dig deeper into player and team tendencies and examine how each approaches the opposition, which he has written about at his own website, Sabermetric Musings. He hopes to use his skills and interests to contribute to the baseball discourse at large, as well as the website that played such a big part in making him the baseball observer he is today.

Vladimir Guerrero Jr. is a supremely talented hitter. In this season’s early going, he has already hit a ball 114.1 mph, swatted a home run, and has a couple of RBI to his name. Prior to his call-up in 2019, Eric Longenhagen and Kiley McDaniel rated him as the best prospect in baseball with a 70 Future Value. If you go to The Board, only five other players since 2017 have received such a grade: Wander Franco (now an 80), MacKenzie Gore, Gavin Lux, Yoán Moncada, and Shohei Ohtani. His specific combination of future tool grades, consisting of a 70 hit tool, 70 game power, and 80 raw power, is unrivaled in the dataset, a unique blend of elite bat-to-ball skills and game-changing power. At 19, he posted a 203 wRC+ in Double-A and a 175 wRC+ in Triple-A. The latter is especially impressive given that the average age of a Triple-A player is 28.

With those things in mind, you might say that what we have seen from the young phenom thus far is a bit disappointing. In 757 plate appearances through his age-21 season, Guerrero has posted a 107 wRC+. That places him 112th amongst all hitters since 2019 (for players with at least 500 plate appearances), sandwiched between the aging Robinson Canó and Omar Narváez. But I would note that context is key. Guerrero is one of only 10 players to receive 500 plate appearances through age 21. On that list, he ranks seventh in wRC+ behind Juan Soto, Fernando Tatis Jr., Cody Bellinger, Ronald Acuña Jr., and Carlos Correa. One could argue that four of those guys are on a Hall of Fame trajectory while the fifth (Correa) has been one of the top talents in the sport when he is not struggling with injury.

Guerrero is in rare company given the amount of big-league time he has logged at such a young age; that is an accomplishment in and of itself. But we are still left wanting more. How can he unlock his generational tools and become the hitter we hope he can be? I would argue the most glaring potential adjustment is to his swing plane. In 2019 and ’20, Guerrero posted groundball rates of 50.4% and 54.6%, respectively. The following represents his rolling average groundball rate in 25 groundball samples:

A whopping 68.5% of these samples yielded groundball rates above the major league average. Over the past two seasons, major league hitters have produced a .218 wOBA and .244 BABIP on groundballs compared to a .500 wOBA and .344 BABIP on batted balls in the air. Among the group of players with 500 plate appearances the past two seasons, Guerrero ranks 15th out of 226 players in the cohort. The frustrating part of this phenomenon is that he hits the ball exceptionally hard, to the point where if he put the ball in the air at closer to league average rates he would be a candidate to place amongst the league leaders in home runs and overall production.

To get a better idea of how Guerrero compares to sluggers with his prodigious power, I pulled the batted ball data from Baseball Savant (via Bill Petti’s baseballR package) for a select few right-handed hitters who posted comparable maximum exit velocities to Guerrero in ’19 and 2020. This list includes the following:

Top Right-Handed Sluggers 2019-20
Player Max EV 2019 Max EV 2020
Aaron Judge 118.1 113.1
Fernando Tatis Jr. 115.9 115.6
Gary Sánchez 119.1 117.5
Giancarlo Stanton 120.6 121.3
José Abreu 117.9 114.0
Marcell Ozuna 115.9 115.6
Mike Trout 116.6 112.9
Nelson Cruz 117.0 114.4
Pete Alonso 118.3 118.4
Ronald Acuña Jr. 115.9 114.8
SOURCE: MLB Advanced Media

Max exit velocity is our best indication of a player’s raw power. We do not have to worry about a sufficient sample of plate appearances to see how that power plays in the game; all we care about is how hard the player can put the ball in play if he makes optimal contact. You, the reader, might gripe that it is difficult to use max exit velocity to gauge a player’s power. How do we know this is truly the hardest he can hit the ball? To that I say, yes, smart reader we definitely do not know if a player’s maximum exit velocity is actually the hardest he will hit the ball. But, I will say, we can reasonably confident that we are in range fairly quickly, based on research from Alex Chamberlain.

The main comparison I am interested in is the differences in approximate attack angle between these players. The concept was outlined in great detail by Jason Ochart at Driveline in this 2018 post, but the TLDR is it is the vertical angle (which is associated with the launch angle of a batted ball) of the bat as it goes to impact the baseball. Hitters can measure it with bat sensors or by parsing video.

Unfortunately, we do not have this information for major league hitters in games because they do not walk up to the plate with sensors on their bats. Instead of throwing our collective hands up, however, we can approximate attack angle with the data we do have access to. And fortunately, that has already been done. Back in 2017, David Marshall wrote an amazing piece on the Community Research blog here at FanGraphs reverse engineering attack angle from Statcast data. He concluded his post with an elegant linear equation approximating attack angle based on the launch angle of the top 20% of a player’s hardest hit batted balls. Anthony Shattell has also posted about data of this nature in the past, and I would highly-recommend scrolling through his feed for some batted ball related visuals; he uses the top 10% of hardest hit balls for his attack angle approximations. For this analysis, I arbitrarily took the top 5%. One might quibble with such a choice, but I think it gets the same point across.

Here are the estimated attack angles for the hitters in the table above based on my filtering criteria:

Attack Angle of Vlad EV Comparables
Player Attack Angle
Pete Alonso 15.62
Aaron Judge 9.86
Giancarlo Stanton 8.74
Nelson Cruz 14.85
José Abreu 11.26
Mike Trout 16.94
Gary Sánchez 16.11
Marcell Ozuna 15.23
Ronald Acuña Jr. 17.86
Fernando Tatis Jr. 15.25
SOURCE: MLB Advanced Media

Stanton has the flattest swing in this group with an estimated attack angle of 8.74 degrees. Guerrero is even lower at 8.71 degrees. Stanton and Judge stick out in that they hit a ton of home runs but have noticeably flatter swings then the rest of the group. They make up for those flat swings by hitting the ball harder than anybody else in baseball. In the Statcast era (since 2015), Stanton has hit 28 balls over 118 mph, the most in the majors. Judge sits second with 10 (he was not a full-time regular until 2017). Third, despite his lack of experience in the big leagues, is Guerrero. If you just look at 2019 and ’20, Vlad is tied for the most with Stanton. Guerrero and his power are in rare company. What’s more, Stanton and Judge have career strikeout rates of 28.1% and 31.4%. Guerrero’s sits at just 17.0%. Even though he doesn’t have quite the same amount of juice on contact as the Yankees outfielders, he makes up for it by putting the ball in play much more often, albeit on the ground. Stanton and Judge have career groundball rates of 42.2% and 38.5%, respectively, with the former about league average and the latter about a standard deviation below it.

Guerrero is still a step behind Stanton and Judge with regards to power, so any large increase in extra base hits (where he has been slightly above league average in terms of the percentage of his total plate appearances) will have to come from either hitting the ball harder or putting more balls in the air. In my own research, I found that maximum exit velocity peaks around age 26 and average exit velocity on balls in the air peaks around 30. So maybe there is some power Guerrero can still squeeze out of his bat. Given that he is already inside the top 1% in raw power, however, I am dubious of how much room for growth there is in that department. What about swing plane? There is precedence for young hitters changing their distribution of batted balls.

More often than not, these young talented hitters saw performance boosts when putting the ball in the air more. That is not to say Guerrero will definitely see a bump in production if he focuses on hitting the ball in the air. It could mess with his swing for all I know. But I do believe that there is room for him to add some loft in his swing, even at the expense of more whiffs. His strikeout rate is close to six percentage points below the league average. There is a trade-off to be had there that can make him the fearsome hitter we all believe he can be.

Guerrero is still very young and has a lot of room to grow as a hitter. The projection systems seem to agree. The FanGraphs Depth Charts projections see him putting up a .360 wOBA in 2021, 23rd in baseball. THE BAT X, which to my knowledge most explicitly leverages existing Statcast data, is even more optimistic. It sees a .376 wOBA in Vlad’s future, placing him 11th in the league and sandwiching him in between Yordan Alvarez and Judge.

When you consider his pedigree coming into the majors, his high-end bat control (as evidenced by his strikeout rate), and his nearly unmatched power, I still think these projection systems are a little light on what to expect from Vlad Jr. going forward. His combination of skills should put him in the conversation to be among the best hitters in baseball, the type who is in the MVP conversation throughout his 20s. Let’s hope he can make the necessary adjustments and grow into that kind of player starting this season.