The changeup is Erlin’s primary offspeed pitch, and despite an awful 166 wRC+ against it in 2019, it may be his most effective pitch for whiffs. It was weighed down by a .455 BABIP in 2019, but generated an O-Swing of nearly 50% and a SwStr% of 20.6%. He may need to increase his zone rate to utilize it more frequently in 2020.
The curveball is Erlin’s top secondary offering. It’s a long looping hook and generates some extremely weak contact, evidenced by a barrel rate of 0% against the pitch. It had a 30.4% strikeout rate without allowing a single walk. With a 40% zone rate, Erlin can utilize this pitch for both called and swinging strikes.
Erlin’s fastball is relatively straight with below-average velocity. It was punished to the tune of a 159 wRC+ in 2019. Erlin may want to decrease the usage of his fastball to under 50% in favor of his changeup or hard slider.
Erlin utilized the slider just over 10% of the time in 2019. It’s a hard slider without much break. It has a below-average SwStr%, but generates a high volume of weak contact. The results may not have reflected the skill of the pitch.
Erlin had been a strictly four-seam guy, throwing it far more than any other pitch. But in 2018 he introduced the sinker, throwing both pitches at a similar rate. The four-seamer was far more effective, with an excellent strikeout rate, though it allowed a few too many home runs.
This is a new addition for Erlin, cut his four-seamer usage in half in favor of the sinker. He should get rid of it. Hitters put up an .867 OPS and 141 wRC+ against the sinker.
The curveball is Erlin’s primary breaking ball, and its the one pitch that didn’t see a usage change when he shifted to the bullpen. It racked up ground balls at solid rate and hitters managed just a .186 batting average against it.
The changeup had been Erlin’s No. 2 offering as a starter, but it fell behind his sinker and curveball in 2018 as he bounced between starting and the bullpen. He should bring it back. The changeup has been a certified Money Pitch for the past four seasons, and had a career-high pitch value last season.
Erlin only threw a slider about once every two appearances last season. It doesn’t move much but gets strikes at a reasonable rate, given the low usage.