Peacock pulled out the change up only 90 times in 2019, which is about how often you will usually see it. With two wicked breaking balls, there is not much need for this fourth pitch that has never been too effective.
Peacock threw his curve seldomly but definitely when it mattered. He struck out over 40% of hitters with the curve (11 Ks on 27 PAs) while only allowing four hits. Despite throwing this pitch in the zone 22.9% of the time, he got batters to swing 35.2%.
Peacock’s fastball has been worse and has been better, but the last two years he has struggled with the long ball. He allows fly balls at a rate north of 50% with a HR/FB above 20%. Batters have been much more aggressive, especially in the zone, which has notably resulted in worse outcomes for Peacock.
By and large, Peacock is a fastball-slider pitcher. His slider has been one of the best pitches in the game, striking out over 30%, but this season his swinging strike rate dropped to 15%. However, he kept the ball in the park with this pitch and kept batters to a sub-.200 average.
Peacock’s slider became infamous in 2017 with its wizardly movement. It posted a swinging-strike rate higher than 20% for the second consecutive season. It had a little bit of a home run problem in 2018, causing the difference between a .191 average allowed and a .436 slugging rate.
Peacock’s two-seam fastball has some incredible side-to-side movement. It’s a good ground-ball pitch, inducing more than 50% ground balls. The amount of balls on the ground limited hitters to just a .375 slugging rate.
The four-seam fastball was the biggest liability in Peacock’s repertoire in 2018. 10 of the 11 hits he allowed on the pitch went for extra bases, leading to a .542 slugging rate despite a .186 batting average against.
Peacock mostly avoids his curveball, and a 19.2% zone rate speaks to a possible lack of command of the pitch.