– The K Zone –
June 16, 2018
Who Got Figured Out, by Ian Joffe
The hot start…and the extended slowdown. The rookie sensation…and the “sophomore slump.” Baseball is made of up and down streaks, and figuring out what causes them can be a secret to understanding the game. Sometimes they come from simple luck of defensive positioning and batted ball location. Usually those kinds of changes in offense will be associated with changes in BABIP. Other times, hitters can make legitimate changes to their swing or approach, although it’s smart to be suspicious of any supposed changes until there’s a large enough sample to confirm that the change made a real difference. In other cases, pitchers start to approach batters in different ways, and the batters become, at least temporarily, befuddled. A pitcher has two weapons at his disposal: Where to pitch the ball and how to pitch the ball. I’m going to focus mostly on the latter, in terms of pitch types, but I’ll also look at simple zone percent to see if a batter has stopped getting balls or strikes.
Often, pitchers will change their approach in response to a hitter becoming surprisingly hot, especially when there’s no clear indication of luck. To see which hitters received major adjustments from pitchers this season, one can look at the difference between the amount of pitches of a certain type they received in April vs. in May of this year. Here are all the qualified hitters whose opposing arsenal changed by at least 7% in at least one pitch, by Pitch f/x data (note that these are changes in percentage out of the total arsenal, not the individual pitch, for example +10% curveballs means the batter used to receive 15% curves and now gets 25%):
Mike Trout: -7.6% Sinkers
Rhys Hoskins: +9.3% Changeups (who Mike interviewed just about a year ago)
Jed Lowrie: -8.8% Sinkers
Freddie Freeman: +10.3% Sliders
Kris Bryant: +8.2% Sliders
J.D. Martinez: +7.8% Changeups, -10.3% Curveballs
Javier Baez: +12.3% Sliders
Odubel Herrera: +8.8% Sinkers
Lorenzo Cain: -10.1% Sinkers
Mike Moustakas: -7.8% Curveballs
Kevin Pillar: +8.7% Sinkers (who we also happened to have interviewed)
Jose Martinez: -7.1% Sinkers
Jose Ramirez: +7.8% Curveballs
Nick Ahmed: +7.6% Sliders
Mallex Smith: +12.5% Four-Seamers
C.J. Cron: +8.1% Sinkers
Nicholas Castellanos: -7.4% Sliders
Evan Longoria: +14.1% Four-Seamers, -10.7% Curveballs
Trea Turner: +7.3% Four-Seamers
Yonder Alonso: -8.9% Sliders, +7.3% Curveballs
Alex Bregman: +7.7% Cutters
Buster Posey: +8.0% Four-Seamers
Scooter Gennett: +8.6% Four-Seamers
Matt Joyce: +10.3% Changeups
Gary Sanchez: +11.4% Curveballs, -8.2% Four-seamers
Giancarlo Stanton: +9.8% Four-seamers
Tucker Barnhart: -8.3% Sinkers
Jose Peraza: +10.6% Four-seamers
Kyle Seager: +7.1% Sliders
Marwin Gonzalez: -8.9% Four-seamers
Michael Taylor: -8.2% Four-seamers
Victor Martinez: -8.2% Four-seamers
Justin Upton: -7.4% Sinkers
Miguel Rojas: +7.1% Changeups
Brett Gardner: +7.5% Curveballs
Adam Jones: +10.4% Changeups
Adam Duvall: -11.9% Sinkers, +7.7% Four-seamers
Edwin Encarnacion: -7.3% Four-seamers
Billy Hamilton: +10.3% Four-seamers, -9.6% Sinkers
Ian Desmond: -7.0% Four-seamers, +8.4% Sliders
Brandon Crawford: -8.2% Sliders, +8.2% Strikes
Lewis Brinson: +9.4% Four-seamers
Pitchers, catchers, and pitching coaches may choose to alter their selection against a hitter because his data shows a weakness on that specific pitch in the past, or a potential hole in sequencing is noticed that can be used to take advantage of the hitter. Surprisingly, however, very few of these changes were shown to have effects. Filtering out the batters whose offensive adjustments were based on BABIP luck, there were only a few hitters who lost at least 20 wRC+ (the best tell-all offensive metric that we have) between March and April:
Javier Baez was unable to keep up in sequences with sliders, losing 46 wRC+ but only 0.016 of BABIP when his rate of sliders increased 12%. Don’t look for too much from the potentially promising young Cub.
Lorenzo Cain‘s changes draw concern based on his recent league change. Pitchers in the NL took a little time to adjust, as Cain had a strong showing in April, but when they realized his weakness against the sinker, they capitalized, and his wRC+ dropped by 33 while his K-Rate rose by 4.3%. His specific case related to the league change is certainly worrying.
Mike Moustakas, who returned to the Royals on a one-year deal after a rough free agency, was quickly put in his place by opponents’ curves, whose increase cost him 37 wRC+ in May. If there’s one player here I’m less worried about, though, it’s Moustakas; I think we know, and pitchers already knew, who he is.
Jose Martinez was a surprise story in April, but a barrage of sliders have slowly started to chip away at his stats, and he, like Moose, lost 37 wRC+ but also experienced a 5.8% rise in strikeouts. Look for more regression as pitchers continue to figure out the young Cardinal.
Matt Joyce fell victim to the changeup this May, which isn’t surprising given his history and swing. Don’t hold your breath of Matt’s career year. In addition to the drop in wRC+, he struck out 10% more often in May than April.
Marwin Gonzalez showed plenty of signs of potential regression last year, especially on Statcast metrics, and as soon as pitchers stopped throwing him fastballs this year, his season collapsed in the form of 32 wRC+ and poor batted ball metrics.
Michael A. Taylor, the Nationals speedster who has stepped in and stepped up in place of several injured Nats looked strong at first, but couldn’t keep up the pace in response to an increase in fastballs and a decrease in offspeed stuff. If he wants to stay in the starting lineup, he’ll have to learn to keep up with velocity.
While there is some worry to be cast on the players above for the rest of the season, it’s even more surprising how resilient the vast majority of hitters were. Most seemed unfazed by the new way they were being treated after early success, and any changes were much more often associated with luck than real factors, like being pitched to differently. And, even for the seven who made the shortlist of concern, there is hope. Repeating this exercise on the 2017 and 2016 seasons showed that there is little reason to worry even for them.
Last season, in 2017, the shortlist was comprised of Michael Brantley, Mike Moustakas (again), Salvador Perez, Tim Beckham, Yasiel Puig, and Randal Grichuk. Inconveniently, only three of those six qualified in the second half: Moustakas, Beckham, and Puig – and none of them had problems. Puig had the second best half of his career, posting a 136 wRC+, and Moose put up a fairly solid 106 mark. Both maintained down-to-Earth strikeout rates too. Beckham also had a great half, with a 113 wRC+, although a higher K-rate and a .353 BABIP suggest that that may not be entirely natural. Either way, if the 2017 crop is any evidence, some guys may just take a while to get used to changes in how they’re pitched to, but will recover eventually.
Running the same program for 2016, eight names were churned out. That list included Anthony Rizzo, Neil Walker, Starling Marte, Chris Davis, Curtis Granderson, Corey Dickerson, and Billy Burns. Four of the eight: Rizzo, Davis, Granderson, and Dickerson, qualified in the second half, and once again, they had a strong showing. Other than Davis, who, to be blunt, isn’t that good anyways, the players each had a wRC+ over 108, topped off, of course, by Rizzo’s 121. Like in 2017, the 2016 slow-adjusters figured it out eventually. Based off what’s happened in the prior two years, I see little reason to worry about this season’s seven. They each may have individual concerns, but the simple fact that they are taking a while to learn how to hit after pitchers realized they were decent has not, historically, been telling of anything. They may be figured out for now, but just wait a month and see.