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It’s still April and Reds manager David Bell is figuring out roles for his relief pitchers.
Alexis Diaz has again been designated the closer, to no one’s surprise. Since being removed from the starting rotation, Nick Martinez has pitched in relief twice, once for four innings and three innings Saturday evening. For retiring left-handed batters, Justin Wilson and Brent Suter are lefty throwers, with Wilson getting the toughest assignments of those two. Suter also can cover long relief as he did today.
The four remaining right-handers have vied for standard set-up duty: Emilio Pagan, Buck Farmer, Lucas Sims and Fernando Cruz. Of that group, Cruz is throwing the most devastating pitch in baseball — a split-finger.
Over the years, the splitter’s place in major league pitching arsenals has swung from triumph to taboo. Today, its roller-coaster journey continues, with a hair-raising comeback and with the Reds’ Fernando Cruz enjoying a front row seat on the ride.
Prominence, demise and revival of the splitter
Baseball historians identify 1908 for when the first splitter (or forkball) was thrown, at the height of the early Dead Ball Era. It was a time when pitchers such as Christy Mathewson and Walter Johnson began to attract fan interest equal to that of hitting stars.
The 1980s and 1990s were peak splitter time. It put Bruce Sutter (1976-1988) in the Hall of Fame. The Astros’ Mike Scott is said to have revolutionized the splitter’s shape, giving it the now-familiar swoop and sink. Baseball historian John Thorn says during the second half of the 1986 season, Scott’s splitter was “as nearly unhittable as any ever seen on a diamond” propelling Scott to the NL Cy Young Award. Then, pitchers like Roger Clemens, Jack Morris, David Cone and John Smoltz used it to devastating success.
Tony Gwynn, maybe the best pure hitter in history, said the splitter was the single most difficult pitch for him.
But over time, a conventional wisdom formed that excessive strain and torque from throwing the splitter led to elbow injuries. Most hitting coaches discouraged it and the pitch fell out of favor due to the perception of health dangers. Because of those concerns, the percentage of splitters thrown in MLB hasn’t exceeded 2.3% in the pitch tracking era.
But maybe the splitter itself isn’t the culprit. As the epidemic of elbow injuries spreads through the sport, research has focused on what factors cause it. A 2016 study of major league elbow injuries looked at fastballs, sliders, changeups, curves, cutters and splitters and concluded that pitch velocity, not pitch type was linked to elbow injuries for major league pitchers.
In recent years, the splitter has mounted a comeback. During the ’23 World Baseball Classic, Team Japan dominated with it. Major leaguers Kevin Gausman and Alex Cobb use it as their primary pitch. Cobb threw 83 (!) of them in a single game — when he came within one out of pitching a no-hitter. Orioles reliever Felix Bautista — maybe the best closer in the game in ’22 and ’23 — threw a splitter 25% of the time.
And, if you were paying close attention last Tuesday, the Reds offense was on the receiving end of Logan Gilbert’s nasty splitter. You might remember seeing this a lot from the Mariners starter that night.
On the Reds staff, Frankie Montas uses the splitter for a quarter of his pitches.
But Fernando Cruz is the Reds pitcher who throws it the most, with devastating success.
Fernando Cruz and splitter emerge in ’23
Our ’24 bullpen preview pointed out that Cruz had been the best Reds reliever (3.45 xERA/3.50 xFIP) in ’23. He led the staff with a 35% strikeout rate, good for the 99th percentile in MLB. Even missing a month with a sore shoulder, the 33-year-old Cruz appeared in 58 games and covered 66 innings.
Here last August, Matt Wilkes analyzed Cruz’s emergence. As Matt found, if you look to statistics that do a better job measuring how a player is actually pitching (xERA, FIP, xFIP, SIERA), Cruz had already been pitching well for several months. Matt put a spotlight on the pitch that was most successful for Cruz, his 81.4-mph splitter.
“Much of the credit goes to Cruz’s wicked splitter. The pitch is almost impossible to hit, boasting an absurd 54.2% whiff rate. That means hitters have missed more than half the time they’ve swung at it this season.”
Cruz finished the ’23 season with a 56.7% splitter whiff rate. Of individual pitches that were thrown at least 400 times last year, Fernando Cruz’s split-finger had the second highest whiff rate, trailing only the Mets’ Kodai Senga’s “ghost-fork” (splitter) at 59.5%.
A month ago, baseball writers at The Athletic described the splitter as a “dark art, poised to takeover baseball.” They began by recounting Fernando Cruz’s journey to master the pitch.
“A decade ago, on a dusty baseball diamond in Puerto Rico, a veteran pitcher shared with Fernando Cruz the secrets of throwing a splitter, a pitch treated like a black-market product, a dark art best learned in the shadows and deployed at one’s own risk. Cruz was a converted infielder pitching in winter ball back home and trying to catch on with a major league organization. By the time the Cincinnati Reds signed Cruz in 2022, he had wrestled the splitter into submission. Cruz made his major league debut at 32. He said he owes it all to the splitter, which has generated a .085 batting average and one of the highest whiff rates of any pitch in baseball.
‘I call it my gift from God,” Cruz said.'”
Cruz has acknowledged the alleged risk to his elbow. But after an arduous career bouncing from minors to international leagues to independent ball, he was motivated (desperate) to find a way to make it to the majors. The split-finger pitch is his golden ticket.
Cruz and the splitter in ’24
In 2024, Fernando Cruz has increased the number of splitters he’s throwing, up from 36% in ’23 to 48%. Has Cruz followed up last year’s astonishing performance with continued success this season?
My goodness. Yes.
That astronomical whiff rate of 57% last year? After today’s two swing-and-misses, it’s 75% (!!) in ’24. Cruz’s splitter remains the backbone of his arsenal, producing an overall whiff rate of 55.4% (best in the majors) and overall strikeout rate of 54.8% (also best in the majors).
You might spot Cruz’s low-ish ground ball rate of 40% and wonder why it isn’t higher. After all, a splitter looks like a fastball before it dives to the ground. It should produce a tidal wave of ground ball outs.
But in Fernando Cruz’s case, batters can’t put his splitter in play. At all. So, no ground balls. And no fly balls. No line drives. Not even a popup or two. Nothing.
Of the 68 times he’s thrown it, the splitter has been the decision pitch for Cruz for 21 batters.
The results?
- 17 strikeouts
- Two walks
- Two ground-ball outs
Note the lack of base hits. His GB% is largely the product of outcomes from his other pitches.
Here’s the (lol) spray chart of balls put in play on Cruz’s splitter in ’24.
Check out this plot (lol, again) of the swinging strikes Cruz has induced on his splitter this year. Note how few are in the strike zone and how many are way, way below it. This doesn’t include the two from today.
As it is for other pitchers, Fernando Cruz’s splitter is an equal opportunity destroyer. He’s thrown about the same number to right-handed batters as to lefties, effective against both. Here he strikes out Mariners’ young superstar Julio Rodriguez on the splitter.
Later, Cruz sits down Rodriguez’s teammate, Cal Raleigh who swings from the left side.
One last chuckle.
Batters are hitting .000/.028/.000 against Cruz’s splitter, with an average launch angle of -14º.
Bottom Line
Treating the splitter as villainous for a generation has taken a toll on its reputation, leading to stigmatization and underuse. Because of that, some analysts view the splitter as an underexploited market inefficiency and advocate pitchers throwing it more often.
Indeed, across the league, the splitter is experiencing a comeback. At the same time, pitchers who throw it must acknowledge and worry about the danger. Felix Bautista recently underwent Tommy John surgery. So did promising Rays starter Shane McLanahan, who threw a splitter 26% of his pitches. The splitter is one of many pitches thrown by Shohei Ohtani, who is recovering from his surgery this season.
That brings us back to Fernando Cruz and his dream job of pitching in the major leagues. Other than drawing a rare walk, opposing batters have been helpless against his splitter. It’s proving hard to hit and impossible to barrel up.
Manager David Bell knows what he has. He’s giving Cruz the toughest assignments. For example, on Friday, with the Reds defending a 2-1 lead in the 7th, the Angels had runners at second and third with one out. Bell called on Cruz (and his splitter). The next two batters didn’t have a chance.
Fernando Cruz, Painting. 🖌️🎨
Dude's nasty. pic.twitter.com/AMIjLDcuZX
— Rob Friedman (@PitchingNinja) April 20, 2024
Fernando Cruz is the best pitcher in the Reds bullpen. He was last year, too.
That success is attributable to his split-finger pitch. Whether Cruz learning to throw the pitch turns out to be a Moneyball gift from God or instead a Faustian deal with the devil and a surgeon, for now it’s giving opposing batters nothing but, well, splitting headaches.
Great article! Thanks.