1. Corey Kluber, Indians
2. Chris Sale, Red Sox
3. Craig Kimbrel, Red Sox
4. Luis Severino, Yankees
5. Justin Verlander, Astros
Take every type of pitch thrown with any regularity (at least 100 at-bats) by every starting pitcher in the major leagues. Now guess which of the many different pitches by the many different pitchers is the toughest to hit. The answer should be obvious to anybody who has watched Corey Kluber pitch even a little bit. The difficulty is in actually naming the most unhittable pitch in baseball. Pitch FX calls it a slider. StatCast calls it a curveball. Kluber calls it neither.
“It’s a breaking ball,” Kluber said.
It’s an alien—like nothing else catalogued by humankind. Kluber has thrown 769 aliens this year and given up 23 hits—that’s one hit for every 33 breaking balls he throws. Hitters have batted .096 against it, the lowest average against any pitch by any starting pitcher.
(Oh, and if you’re wondering which reliever has the world’s nastiest pitch, that would be Kluber’s teammate, Andrew Miller, who throws a slider that has held hitters to a .083 batting average. All the more amazing that in World Series Game 7 last year the Cubs built a 6-3 by pounding Kluber and Miller for a .384 batting average, with 10 hits in 26 at-bats.)
Kluber leads the league in ERA, wins, winning percentage, WHIP, walks per nine innings, bWAR and adjusted ERA.
Sale is your strikeout king, and also has thrown the most innings, posted the best strikeout-to-walk rate and compiled the lowest FIP. He would be a great choice in almost any other year. Alas, his ERA is almost half a run higher than what Kluber has posted (2.27), thanks to Kluber’s teammates. Sale posted a 14.63 ERA in two starts against Cleveland, and a 2.34 ERA against the rest of baseball.