After drawing criticism and having both his mental and physical toughness questioned for nearly two years, Yu Darvish has turned into the Chicago Cubs’ ace. Long known for his exceptionally diverse repertoire, Darvish attributes his recent success his new “best pitch,” a hard knuckle curveball he recently learned from Craig Kimbrel.
Darvish struck out 14 Padres in Thursday’s game, a feat that pushed his ERA under 4.00 and his K total over 200 for the season. He got three of those strikeouts on cutters/sliders, four on fastballs, and — most notably — seven on curveballs.
Prior to Tommy John surgery, Darvish’s “hard curve” was a huge part of his repertoire. But the elbow reconstruction ultimately discouraged Darvish from using the pitch in favor of slower iterations. You can see in the figure below that his average curve velocity was around 80 mph early in his career, but it dipped down to around 73-74 mph after surgery.
Lately, though, Darvish has included that hard curve back into his already diverse basket of pitches, thanks to his new teammate. Notice how Darvish’s average curveball velocity in September is about 2 mph faster than that from previous months.
As we discovered early on, Darvish’s new “Kimbrel curve” is thrown about 2-5 mph faster than his normal curve with 10% more spin. That harder, tighter curveball has more spin than 75% of MLB, so it’s a different look from what either Darvish or most other pitchers in general typically offer.
In less than a month, Darvish learned how to throw a pitch that he now considers his best among at least 10 different offerings. Absolutely insane.