Corey Kluber and Kluberization: Ditching the Four-Seam

If Corey Kluber’s road to the big leagues was long and winding, the reason for his recent success might be short and simple. One day, some time in 2011, the pitcher finally gave up on his four-seam fastball and started throwing a two-seamer. And now you have the current Corey Kluber. A contrite pitcher talking about a simple change doesn’t make for a long interview, but the Corey Kluber Process might be applicable to some other young pitchers around the league.

Kluber does have great offspeed stuff. His change-up (22%), slider (20%), and cutter (15%) are all above-average by whiff rates. That’s no small feat. The list of other starting pitchers with three above-average whiff rates on offspeed pitches is very short: Yu Darvish, Matt Harvey, Felix Hernandez, Tim Lincecum, and Jerome Williams. That last name — the last two names these days? — should give you pause. “All of that other stuff plays off the fastball, if you’re not consistent with the fastball, none of that other stuff is going to be as good,” said Kluber before a game against the Athletics this week.

So, despite having a great mix of secondary pitches, Kluber has had to find his way to the big leagues by improving his fastball. “I was getting hit around and was having trouble working consistently down in the zone,” said Kluber of 2011, when he had an ERA over five in Triple-A. Big league pitching coach Mickey Callaway and then-Triple-A pitching coach Ruben Niebla conferenced with the pitcher and advocated the two-seamer. The change has taken to Kluber — “I hardly ever throw the four-seamer any more.”

Now he’s got a sinker that coaxes mostly grounders. Now he’s got three pitches that go for grounders. The fastball is the most-thrown pitch in baseball, and now he has one. (No, he never discussed the idea of throwing his cut fastball as his number one, he said.)

Now the Indians’ right-hander is getting used to the pitch. “It’s a pretty drastic change to throw the ball differently than you’ve thrown it your whole life,” Kluber said, adding that he’s getting more comfortable with it every day despite the change-up being his biggest “feel pitch” that requires as much practice. A little uptick in velocity on the fastball and improved walk rates seem to reflect that he’s good with the two-seamer now.

This transformation, at least in retrospect, seems so easy. Three main fastball grips are there for pitchers to use, and they’ve been fiddling with that pitch the longest in their lives. The fastball is the first thing you’re allowed to throw. It also builds up a sample fairly quickly — are there other Klubers out there? Could some bad fastballs undergo the Corey Kluber Process?

I suppose we’d be looking for a four-seamer with a bad whiff rate on a pitcher that doesn’t already throw many two-seamers. Taking only those starters that threw more than 750 four-seamers last year, and then sorting those for the worst whiff rates, you get 20 pitchers who get fewer than 4.5% swinging strikes on their four-seamer (the average four-seamer in that group got a 6.7% swinging strike rate). Here are those 20, with their number of two-seamers listed in the last column.

I don’t know that Joe Blanton and Jeremy Guthrie would really be in the same class as a young Kluber. They’ve probably made their bed by now.

Even among the younger names, though, it’s hard to spot someone with the offspeed resume that Kluber had when he made the change to his fastball grip. Scott Diamond has actually been throwing more two-seamers lately by Brooks Baseball (the numbers above are from our PITCHF/x database) and they are getting 63% ground balls. Though he only has the plus curve otherwise, it could make him more valuable than he was in the past. Considering how good Tyson Ross‘ slider is, and the fact that his 200 or so two-seamers got a 73% ground-ball rate, and that his four-seam didn’t get the whiffs you’d like, maybe more sinkers would serve him well (despite the platoon splits).

Justin Grimm has a good curve, slider and a change-up he can use for grounders. His four-seam didn’t get whiffs or grounders last year, and his two-seam got 63% grounders. By Brooks Baseball, Paul Clemens didn’t throw a two-seamer despite a bad four-seamer and a good change and curve — with his poor ground-ball rate, he might be a prime candidate for Kluberization. Tom Koehler gets good whiffs on a change and slider combo, but his four-seam ended up on this list. These might be your best Klubers, looking for a way to make it in the big leagues despite a bad four-seamer.

Try the two-seamer. It just might save your career.