Thornburg’s changeup did him no favors in 2019, despite a 18.6% swinging-strike rate and weak contact numbers. The pitch yielded a .511 opponent WOBA and 234 wRC+, thanks to high extra-base hit and walk numbers.
Thornburg regained some efficiency in his curveball numbers in 2019, with a respectable .266 opponent WOBA and 74 wRC+, though a high contact rate and weak 7.0 swinging-strike rate suggest these numbers may have been a mirage.
Thornburg’s bread-and-butter was more like a can of baked beans in 2019, with opponents registering a .426 WOBA and 179 wRC+ against the pitch. A 23.4% strikeout rate is among the highest of Thornburg’s career, but a 6.2% swinging-strike rate suggests that the pitch ain’t fooling anybody these days.
Thornburg’s primary offering is his four-seam fastball. After successful results in 2017, he lost 1.5 mph of the fastball and could not generate swings and misses. Thornburg’s fastball allowed a wRC+ of 165 largely due to the four home runs given up and over 94% contact rate.
Thornburg’s curveball is his primary breaking pitch. The movement and plate-discipline numbers have been consistent year to year. However, Thornburg saw a dip in pitch value due to an extremely unlucky .421 BABIP.
The least thrown pitch in Thornburg’s arsenal is his changeup. After successful results in 2017, the changeup had decreased chase and swinging-strike rates in 2018. While the results were not great, Thornburg is able to throw the changeup for strikes, and it should be utilized more often, as his fastball has lost velocity and effectiveness.