4. Brandon Woodruff, Milwaukee Brewers
Woodruff established himself as one of the best pitchers in the game in 2021. The righty made 30 starts and pitched 179.1 innings. He allowed 130 hits, 51 earned runs, 43 walks, and struck out 211 batters. His ERA was 2.56, his FIP was 2.96, his WHIP was 0.97, and his ERA+ was 166. He finished 5th in the Cy Young voting.
His Baseball Savant page is great as well. He is particularly adept at missing bats, finishing in the 92nd percentile in average exit velocity and 90th percentile in hard hit rate. The lowest percentile ranking he finished in was 66th in his whiff rate. In his worst category, his was still 16% above average. Not many pitchers can say that.
3. Walker Buehler, Los Angeles Dodgers
Buehler had his best season in 2021. He made 33 starts and pitched 207.2 innings. He allowed 149 hits, 57 earned runs, 52 walks, and struck out 212 batters. His ERA was 2.47, his FIP was 3.16, his WHIP was 0.97, and his ERA+ was 165.
Buehler doesn’t have the huge strikeout numbers that typically are associated with aces. He averaged just over a strikeout per inning, finishing the season with 9.2 K/9 and in the 65th percentile of strikeout rate. His strength is the spin rates of his pitches, finishing in the 94th percentile in fastball spin and in the 91st percentile in curveball spin. These spin rates lead to a lower quality of contact, which is seen in his 87th percentile in xwOBA.