Zimmermann’s changeup has lost over two inches of horizontal movement over the last two years and it shows in the results. It’s doesn’t get nearly as many chases (26.9 O-Swing%, down 22.4%) or whiffs (2.7 SwStr%, down 8.7%) and as a result got hit pretty hard (.375 AVG, 113 wRC+).
A decent pitch in 2018, Zimmermann’s curveball fell apart in 2019, worth -5.7 pVAL at season’s end. It still had good peripherals for the most part at it boasted a 47.3 O-Swing% and a 13.2 SwStr%. Unfortunately the results didn’t mirror that as it may have gotten BABIP’d to death thanks to a .418 BABIP. Either way the pitch surrendered a .333 AVG, .831 OPS, and a 127 wRC+.
Zimmermann’s fastball fared better in 2019 than in years past (-1.9 pVAL in 2019, -12.7 pVAL in 2018, and -23.3 pVAL in 2017) but it still got hit pretty hard (.286 AVG, .276 ISO, 144 wRC+). It just doesn’t have the velocity (90.8 mph) or movement necessary to fool hitters anymore.
Despite gaining additional movement in 2019, Zimmermann’s slider lost nearly a full mph in velocity and couldn’t really fool anyone despite solid peripherals (42.9 O-Swing%, 44.8 Zone%, 10.7 SwStr%). This pitch got shellacked as it surrendered a .313 AVG with a .908 OPS, .250 ISO, and a 146 wRC+.
Zimmermann’s heater took a small step forward last season, up to a -12.7 pVal. It gives up a ton of line drives and fly balls, leading hitters to hit .313/.361/.620 last season. It has been particularly bad the past four years, especially at giving up home runs.
The slider on the other hand, was very effective. It was near Money Pitch status with a 14.7% swinging-strike rate, and solid zone and outside swing rates. The majority of contact against it was weak, though it did allow six home runs.
The curve went from terrible to not bad, as Zimmermann regained some lost movement from the prior year. Hitters hit .263 off the pitch, but it flashed good swing-and-miss ability. It does give up plenty of fly balls though, which led to a .238 ISO.
We don’t see much of Zimmermann’s changeup, and for good reason. It was OK at generating whiffs, but opponents hit .417 off the pitch. It is clearly behind his other pitches in the pecking order.
Zimmermann rarely throws the two-seamer, focusing more on his four-seamer for results. Two-seam only comes out less than 3% of the time.