TORONTO — In Game 6 of the World Series on Friday, two of the foremost practitioners of the pitch that has defined October will duel at Rogers Centre. Los Angeles Dodgers right-hander Yoshinobu Yamamoto is trying to save his team’s season, and Toronto Blue Jays right-hander Kevin Gausman is trying to win his franchise’s first championship in more than 30 years, and both will rely heavily on the split-fingered fastball, an offering that for almost 20 years teetered on the brink of extinction in Major League Baseball.
The rise of the splitter over the past half a decade — fueled by the emergence of elite pitching from Japan, where the the offering is a standard part of nearly every pitcher’s arsenal, and the softening on its use by MLB teams that at one point had forbid the pitch, fearful that it directly led to elbow injuries — has transformed baseball even more than the cutter and sweeper once did. Because it’s a superior pitch to all of them.
“If you can throw it near the strike zone,” Clayton Kershaw said, “it’s the best pitch in the game.”
In recent years, Kershaw began throwing a split-change, finally finding a comfortable variation of a changeup after spending his 18-year future Hall of Fame career in search of one. He is far from alone. This postseason, 32 pitchers, representing nearly a quarter of playoff hurlers, have thrown splitters. Since the advent of pitch tracking in 2008, the highest percentage of splitters thrown among overall pitches in October was 3.2% last year. Most seasons, it ranged between 0.2% and 2%.
This October, 6.8% of all pitches have been splitters, a staggering number that reflects the game’s wholesale embrace. It’s not just Gausman (who has thrown the pitch 41.4% of the time in the playoffs) and Yamamoto (24.7%). Toronto rookie Trey Yesavage dominated the Dodgers with his splitter in Game 5. Shohei Ohtani, who will pitch in Game 7 if the Dodgers win Friday’s battle of the splits, throws a vicious one. Blue Jays closer Jeff Hoffman could set off a celebration with one. The same goes for Dodgers closer Roki Sasaki, whose splitter dances in all directions with perilously low spin, like a souped-up knuckleball.
“It’s kind of one of the few pitches I thoroughly believe a hitter can know it’s coming and still get out,” Gausman said. “I’ve always felt like the changeup is the best pitch in the game because it looks like a fastball, and anything that looks like a fastball and isn’t is really good. So, I think that’s why you’re seeing a lot more guys do it. I’m happy to see a lot more starters do it because it was always kind of more of a reliever pitch. So, to me, it’s exciting to see guys like Yamamoto throw it a lot.”
The splitter is the evolutionary descendant of the forkball, which dates back to the 1910s. Whereas a forkball was jammed as deep as possible between the index and middle fingers, the splitter offers more leeway for pitchers to find comfort. It is not a discriminating pitch like the changeup, which necessitates pronation — the internal rotation of the forearm that leaves the thumb facing down and the pinky up after release — something with which Kershaw and others struggle. It’s quite simple, actually: put the ball between two fingers, support it with the thumb, throw it with the arm speed of a fastball and let the grip do the work.
Closer Bruce Sutter learned the splitter in 1973 and rode it to the Hall of Fame, inspiring the next generation to throw the pitch that looks like a fastball, only to die as it approaches the plate. Mike Scott won a Cy Young with it. Roger Clemens, Curt Schilling and John Smoltz pitched into their 40s thanks to it. By the time their careers ended in the 2000s, though, the splitter was made into a scapegoat for failing elbow ligaments across the game. Some had the gumption to keep throwing it. Most were discouraged, turning splitter into a four-letter word.
The lack of splitters thrown led to a knowledge gap, Dodgers pitching coach Mark Prior said, “and I don’t think a lot of people knew how to teach it. If you were around a guy who threw it, maybe you can mess with it. If you weren’t, I don’t even remember anybody I was with who threw splits. So, it was something you didn’t even mess around with.”
The arrival of Masahiro Tanaka to the New York Yankees in 2014 ushered in a new generation of the splitter. And technology aided its rebirth. Super-high-speed Edgertronic cameras allowed pitchers to see how a ball left their hands. TrackMan, the radar-based system that measures pitches’ spin and movement, gave immediate feedback and a granular look at a pitch’s effectiveness.
“Five, 10, 15 years ago, a guy would work on a pitch all year then find out,” Blue Jays pitching coach Pete Walker said. “Looking back, that was fruitless. It was not going to happen. So, we wasted a year of someone’s career working on a curveball, working on a slider or working on a split-fingered fastball. I think now it’s just expedited. We can make that decision with more background on it and more validity to it.”
Compound that ability and desire to learn new offerings with the sport-wide understanding that velocity is the greatest predictor of arm injuries, and teams’ stances on splitters softened. Pitchers jumped at the opportunity to try the splitter, and with good reason.
This postseason, batters are hitting .154/.206/.250 against splitters — the lowest numbers in each triple-slash category for any pitch. In the World Series, the Dodgers are 1-for-22 with 14 strikeouts on splitters. Toronto has thrown splitters 13.7% of the time during the playoffs, a number that figures to jump with Gausman on the mound in Game 6.
The splitter has saved careers — “I’d have been done a long time ago without it,” Dodgers reliever Kirby Yates said — and is more frequently making them. Over this winter, it will be the talk of pitching labs around the sport, with hundreds of professional pitchers at all levels seeing if it works. Already, multiple front office officials said, teams are digging into their pitchers’ movement patterns to see if a splitter would complement their current arsenal. And because of what they’ve learned designing other new pitches, they’ll have a decent idea whether it works sooner rather than later.
“It could be one session,” Walker said. “It could be even before the session, to be honest with you.”
The versatility of the splitter only adds to the allure. Pitchers can throw it extremely hard, like Paul Skenes‘ and Jhoan Duran‘s splinker, a splitter-sinker hybrid. They can aim for a forked, low-spin variety like Sasaki’s, a devastating late-breaker like Yamamoto’s or one like Gausman’s that he can command in and out of the strike zone. They can even use it as a show-me off-speed pitch like Kershaw.
Whatever the form, the splitter is here to stay. As it proliferates, perhaps its utility will diminish. Part of its effectiveness, after all, is its relative rarity. For now, though, it’s still a pitch teeming with mystery — there one second, gone the next.
“You can’t hit it,” Kershaw said. “You cannot hit a good split.”
