How the Kansas City Royals’ Brad Keller rediscovered his slider, and why it’s crucial
The combination of old-school tried and true video breakdown of pitching mechanics along with analysis of data collected by high-speed cameras and Rapsodo machines gave Kansas City Royals pitcher Brad Keller back his slider.
Keller hadn’t looked like himself for the first month of the season. The young ace of the pitching staff with a bulldog temperament on the mound and a dare-you-to-hit-this mentality had given way to an impostor version that seemed to pitch somewhat timidly — erratically, even.
And this new version of Keller got hit harder than Royals fans had ever seen him get hit.
A 6-foot-5, 255-pound right-hander, Keller struggled to explain exactly what was happening during the first few weeks of the season. Instead he fell back on the common refrains of him just needing to be better and needing to attack more.
Well, Keller now seems to have a better handle on what derailed the start of his season. It mostly comes down to one pitch, his slider, and the trickle-down effect it had on his starts.
“We made a lot of adjustments with that thing,” Keller said. “I feel like that’s one of the biggest reasons my season didn’t get off to a terrible start. I really didn’t have my slider. I didn’t have the same bite to it. I didn’t have the same depth to it. We went back and looked at some analytical stuff and really tried to figure out what we were doing different.”
Keller called the slider his “bread and butter” pitch. The last few seasons, his success had been so tied to that slider that there’s a case to be made that it might have been the most important in determining the outlook of the Royals’ season.
Through his first six starts of this season, opponents were batting .360 and slugging .590 against Keller. He’d given up four home runs and walked 12 in 22 1/3 innings while carrying an 8.06 ERA.
Keller, 25, said the turning point was a bullpen session after a start against the Minnesota Twins on May 2, the beginning of the Royals’ 11-game losing streak. Keller gave up seven runs (two earned) on six hits, including two home runs, in 4 1/3 innings at Target Field. All seven runs came in one inning.
First, pitching coach Cal Eldred, bullpen coach Larry Carter and Keller took a close look at video and compared Keller’s mechanics from last year to this year and noticed that his front side was flying open and he was inconsistent with his release point.
Then the analytical data added further context.
“I was losing depth on it,” Keller said. “It was becoming more of a horizontal slide, which hasn’t really ever been my slider. So we just kind of went back, threw a bullpen, seeing if it was the right release or the right depth. We talked back and forth and after the bullpen got the report back and compared it back with the reports from last year.”
Keller said it was “a first” for him, diving into the data to figure out how to engineer the shape of his slider the way it had been when he was most effective. He found the process “very beneficial.”
The process was similar, without the emphasis on analytics, to what he, Eldred and Carter had done during the shutdown last year.
While spring training was on break in 2020, Keller took the opportunity to fine-tune mechanics via numerous bullpen sessions and FaceTime calls with his coaches. They went over video from those sessions and he got his slider to a place where he put up several dominant outings during the truncated 2020 season.
“We basically went back and looked at some of the videos from then and understood what we were trying to do and really found out some interesting stuff about what I was doing then that I didn’t do this year — (things) that I thought I was doing,” Keller said.
Then, Keller got off to a solid start against the hard-hitting Chicago White Sox two starts ago at Kauffman Stadium. He ended up with a quality start, allowing three runs in six innings. He’d gone into the sixth inning having held them to one run through five.
His next start came against that same White Sox club, but in Chicago, where they’d battered him earlier in the season and Yermin Mercedes hit a 485-foot home run on a slider that left most of the baseball world gawking.
In that start this past Friday, his second consecutive against the White Sox, Keller ran into his hiccups early but also earned the win. He struck out seven and allowed two runs on five hits in five innings as the Royals snapped out of their losing slide.
He felt the difference with his slider. He was more confident, and he threw it and got outs with it even when hitters were sitting on it or looking for it. It kept them off his fastball and prevented the type of loud, head-snapping contact hitters had been getting against him earlier in the season.
“I’m watching adaptability,” Royals manager Mike Matheny said. “Where a guy has learned and before I think he would even try and go harder or try and manipulate the fastball a little bit more instead of trusting his second-best pitch to get him back into counts and get him back in a good rhythm. It’s amazing how a pitcher kind of finds that over time.”
Matheny said finding the feel for the slider has helped Keller make adjustments and get a feel for his fastball at times. His ability to “audible” midstream is something that will serve him well in the future.
