Where has Kluber's breaking ball gone?

Righty no longer leaning on breaker, leaning fastball

Alex Hooper
October 06, 2018 - 10:58 am
Oct 5, 2018; Houston, TX, USA; Cleveland Indians starting pitcher Corey Kluber (28) reacts after Houston Astros third baseman Alex Bregman (2) hit a solo home run during the fourth inning in game one of the 2018 ALDS playoff baseball series at Minute Maid

© Troy Taormina-USA TODAY Sports


Cleveland, OH (92.3 The Fan) – What ever happened to the curveball revolution?

The so-called response to the elevation revolution never actually happened. If anything, it was more of a slider revolution, if a 1.1% increase league-wide merits such a distinction. Sliders increased in MLB by that margin from 15.2% in 2016 to 16.3% 2017, while curveballs “jumped” from 10.2% to 10.6%.

Any curveball revolution seemed to be confined to the Cleveland Indians, who jumped from 6th place in curveball usage at 13% in 2016 to 1st place in 2017. The margin by which they led at 17.1% was 2.2%, more than the distance between the 2nd place Los Angeles Dodgers and 8th place San Francisco Giants.

Cleveland’s all-world staff dropped back to 2nd in 2018, using curveballs at 15.9%.

Corey Kluber threw his curveball just 20 times out of 87 offerings in Friday’s ALDS Game 1 loss to the Houston Astros. Of those 20 pitches, the righty picked up five whiffs and five called strikes. Of the six hits Kluber allowed, including four home runs, none came by way of the breaking ball.

Of course, Kluber’s curveball has been among the best pitches in all of baseball since 2014. It has been the best curve in the game by FanGraphs’ weighted curveball metric in four out of the past five seasons, the lone holdover being the 2015 season in which he finished behind Seattle’s Felix Hernandez.

The pitch was again the best curveball in baseball in 2018, but surprisingly came at a lower clip. Kluber’s peak month of usage in 2018 was 24.1% in July, but since Kluber’s month-long DL trip in 2017, it ranks just 8th-most in a 12-month span.


(Kluber’s breaking ball registers as a slider in the graph above.)

So why has the two-time Cy Young winner scaled back on his best pitch?

Some of the Indians’ dip in curve usage has to do with personnel. Less of the curve-reliant Josh Tomlin and more of slider-heavy pitchers like Mike Clevinger and Adam Plutko, will do that.

Could it also have something to do with departed pitching coach and current New York Mets Manager, Mickey Callaway? Probably.

The Mets, without Callaway, sat 20th in curveball usage in 2017 at 9.3%. Under their new manager, that number jumped to 12.6%, sitting 8th in the league.

Kluber’s spike in breaking ball, whether it is a curve or a slider, coincided with the rest of the Indians staff doing so under Callaway before his exit. Since Callaway’s departure, Kluber’s usage has regressed towards his average 18.9% curveball usage.

Not every pitcher in the Indians clubhouse was sad to see Callaway go, but it cannot be argued that Callaway got the best out of Kluber in his time in Cleveland.

While Callaway had a specific plan that was the guideline for each pitcher, new Pitching Coach Carl Willis began the season by talking about how he wants things to be more of a combined effort. Those quotes were more directly used in reference to Trevor Bauer, but Willis expressed similar sentiments about Kluber when speaking to David Laurilla of FanGraphs.

Kluber likes to do things on his own. He’s very in tune with his delivery,” Willis told FanGraphs. “We have looked at a lot of data during the course of this season, just to maintain his optimal delivery and find the keys to that delivery.

“I always felt, watching him from the other side… everybody always talks about how devastating his breaking ball is. The one thing I saw when he pitched against (the Red Sox) was his ability to command the fastball. You do those things by repeating your delivery.”

That command was absent on Friday afternoon, and the Astros made him pay.

It should come as no surprise that when a pitching coach says a pitcher ‘likes to do things on his own,’ that his tendencies would regress to the norm upon a change. Especially when the variable is a coach who liked things done a certain way.

Also to Willis’ quote that Kluber is ‘very in tune with his delivery,’ consider that the righty’s delivery has been ever-evolving, and only more so under his new coach.

It would be hard to say that Kluber has not been himself under Willis. His numbers were close to the norm over the full scope of the season, but there was a considerable rise in his home run rate, jumping to 1.05 HR/9 in 2018. Hitters are also keying in on trying to elevate the ball.

It is easier to say that Kluber has altered his approach, and these are the aspects in which they’ve seemed altered the most.

Perhaps the game plan against the Astros was to attack with fastballs up in the zone to offset the elevation approach. Houston has been best against curveballs and changeups in 2018, but at the very least, that approach did not work Friday.

If Kluber does not get a second crack at the Houston lineup in the ALDS, his Game 1 outing will be largely trivial, especially if the Indians offense continues its current playoff form.