Lance McCullers increases curveball usage, dominates first start

Since first breaking the Houston Astros’ starting rotation in 2015, Lance McCullers Jr. has always been one of the most talented starters in baseball. Yes, McCullers is no Clayton Kershaw or Max Scherzer. He was not even as valuable as, say, his teammate Charlie Morton, who has not really ever been considered an ace. But McCullers is ultra-talented.

Among starters with at least 300 innings pitched from 2015 to 2017, McCullers ranked 12th in baseball in strikeout percentage, in front of Madison Bumgarner, Jake Arrieta, David Price and many others. McCullers’ ace potential stems from his fastball, which has averaged between 94-95 MPH throughout his career and has reached 99.

While McCullers does boast heat that can blow by hitters, it’s not his best weapon. His curveball — historically thrown just as often as his fastball — is what gives McCullers another offering to strike out hitters. And he’s been quite successful. Over 118 ²⁄₃ innings last season, McCullers had the 10th-highest swinging-strike rate on his curveball across all pitchers.

McCullers famously threw 24 straight curveballs in Game 7 of the 2017 ALCS to beat the Yankees, in what went on to be his most successful outing of the postseason. After McCullers walked Todd Frazier in the eighth inning, in an at-bat in which he did not throw a single curveball, he ditched the fastball and recorded the game’s last six outs — Chase Headley, Brett Gardner, Aaron Judge, Didi Gregorius, Gary Sanchez and Greg Bird — with nothing but the curve. And, as we all know, the Astros went on to win the World Series.

McCullers’ curveball grip even graced the cover of Sports Illustrated last May, in Tom Verducci’s story about the pitch’s resurgence.

Taking from his dominance at the end of the ALCS, McCullers provided a steady diet of curveballs in his first start of 2018 against the Texas Rangers. He threw 51 curveballs in his 91-pitch start on Saturday. That 56.04 percent curveball rate is the fifth-highest of any outing of his career.

Those curveballs were pretty deadly, too. Thirty-five of them (68.6 percent) went for strikes — including 10 called strikes (19.6 percent) and 11 swinging strikes (21.6 percent). On a day when his four-seam fastball and changeup weren’t quite as sharp as usual, those curveballs made all the difference.

Undoubtedly, this strategy worked for McCullers. He pitched 5 ¹⁄₃ innings, allowing four hits and two runs, with 10 strikeouts and just one walk. By Baseball-Reference’s Game Score metric, this was McCullers’ best regular-season start since June 24, 2017, a span of eight starts.

It’s too soon to tell whether McCullers is sticking with this increased curveball usage long-term. After all, it was just one start. But this is something that is certainly worth watching going forward, and if McCullers continues this trend, it could produce results similar to how he pitched this weekend against the Rangers.

Devan Fink is a Featured Writer for Beyond The Box Score. You can follow him on Twitter @DevanFink.