His least-utilized major pitch in 2019, Williams’ changeup continued to be whacked around. A .366 WOBA and 135 wRC+ are the worst numbers in his arsenal, and a pitiful 4.2% strikeout rate suggest that what was once a punch-out pitch for Williams, may be becoming a boat anchor
Williams continued to toss the odd curveball, throwing 22 in 2019. One of those 22 led to a home run, which distorted the pitch stats somewhat – though a 40.9% swing rate suggest he’d be better leaving it in the bullpen
Coming off a 2018 in which his four-seamer yielded a stellar 16.0 pVAL, the pitch plummeted in 2019, despite equal-to-better contact and swing numbers. Disproportionate fly ball (46.1%) and HR/FB (14.0%) ratios on the pitch are the likely culprits, and a bounce back in 2020 is possible
Williams is excellent at limiting free passes with his slider, boasting a near-perfect 0.8% walk rate to pair with a 25.8% strikeout rate. With a .258 xBA, .447 xSLG, and .298 xwOBA, Baseball Savant notes some unluckiness in Williams’ slider results (.309 BAA, .528 SLG, .348 wOBA).
Williams’ fastball may seem pretty bland, but it was an outstanding pitch for him in 2017 and 2018 (12.3 and 16.0 pVal). His willingness to pitch to contact has worked out for him, as he’s generated a great infield fly ball percentage of 26% both years. Although this isn’t a strikeout or putaway weapon, Williams has consistently produced outs with this otherwise unremarkable pitch.
The sinker is Williams’ main secondary pitch, and for good reason. He uses the pitch to keep the ball in the yard/on the ground, a sign of a good sinker. The velocity and movement on this pitch deteriorated from 2017, but he was still able to post a good ground-ball rate (53%) and overall weak contact.
Williams’ change was not a good pitch for him in 2017 (-3.4 pVal). Unfortunately, it was even worse in 2018 (-5.4 pVal). He lost 2 mph and over 2 inches of overall movement on the offering, allowing hitters to be more selective (swing rate decreased) while simultaneously hitting the ball more often and with higher authority (LD% and contact% significantly increased). Don’t be surprised to see Williams’ usage of this pitch take a dip in 2019.
The slider was Williams’ go-to strikeout pitch. Not to say he racks a whole lot of those up, but he was able to generate his highest SwStr (12.5%) using the slidepiece. It was a much better offering than his 2017 version, mainly because of a significant increase in both horizontal and vertical depth. The Pirates’ #3 must continue to use this pitch to keep batters off balance, his other deliveries are too straight to induce strikeouts.