Pirates A to Z: Mitch Keller reinvented his pitch repertoire, delivered breakthrough season

During the offseason, the Tribune-Review will offer Pirates A to Z: An alphabetical, player-by-player look at the 40-man roster, from outfielder Miguel Andujar to pitcher Miguel Yajure.

Player: Mitch Keller

Position: Pitcher

Throws: Right

Age: 26 (April 4)

Height: 6-foot-2

Weight: 220 pounds

2022 MLB statistics: Went 5-12 with a 3.91 ERA and 1.396 WHIP, 138 strikeouts and 60 walks in 159 innings over 31 games, including 29 starts.

Contract: First year of arbitration eligibility.

Acquired: Drafted in the second round in 2014.

This past season: When Keller went looking for what was missing in the majors after three consecutive years as the Pirates’ top prospect, the search started with rediscovering the velocity on his four-seam fastball.

Through 39 starts in his first three seasons, Keller was 7-17 with a 6.02 ERA and 1.72 WHIP. He was demoted to Triple-A Indianapolis during the 2021 season, and saw the velocity on his heater drop to 93.8 mph.

As Keller’s velocity dipped, so did his confidence. He worked with Tread Athletics, a North Carolina-based pitching development company that custom-builds throwing programs, and touched 100 mph in the offseason.

Keller’s confidence returned but the results were up and down. He was 0-3 with a 6.62 ERA and 1.64 WHIP in four starts in April and was 0-5 with a 6.61 ERA by May 13.

“I thought I did pretty well in the first month, just some bad luck here and there,” Keller said. “Just seemed like anything was falling through.”

Where that would be devastating to Keller in previous seasons, he simply went back to the lab and reinvented himself. Keller moved to the bullpen for two games, added a sinker to his repertoire and started leaning more on a sweeping slider as his putout pitch.

Mitch Keller, 84mph Wipeout Slider. ???? pic.twitter.com/Lrt0CW4MiG

— Rob Friedman (@PitchingNinja) September 27, 2022

The change started when Keller allowed two runs on two hits and five walks while striking out five in five innings in a 5-3 win at the Los Angeles Dodgers on May 31.

“Watching Mitch over the last couple years and doing what he’s doing right now, that’s one that hits you heavy in the heart in a good way because you know the struggles that he’s had,” Pirates pitching coach Oscar Marin said. “To be where he’s at right now, it’s a big win for him. We’re really proud of him because of that.

“It wasn’t easy the way he did it, either. Obviously, throughout the offseason he got his power fastball back and came into spring training pretty confident that he did just that. … The work to maintain his stuff where he’s at is huge. We’re really proud of him because of that. He deserves a lot of credit just for sticking with that process to continue to trust when the game asks him to do something. It was asking him to make a change, and he did it.”

Over his final 22 starts, Keller went 4-7 with a 3.22 ERA, 106 strikeouts against 45 walks and allowed nine home runs. He made a dozen quality starts over that stretch, including a 10-strikeout performance in a4-2 win at Milwaukee on Aug. 30 and tossing six scoreless innings in an 8-2 win over the New York Mets on Sept. 6.

“Just proud of myself for how I hung in there and kept going,” Keller said. “I know I’m a good pitcher. I know I’ve done it in the past. Just felt really good after that point.”

What the Pirates were most impressed with Keller is how he handled adversity. Pirates manager Derek Shelton noticed the change in Keller’s outlook, especially how he handled adversity.

“The No. 1 thing that’s jumped out to me is his demeanor,” Shelton said. “Every time he takes the mound, he expects good things to happen. That’s something you have to develop at the major league level. Mitch in the past has been in situations where he may have doubted that something good was going to happen and he had to execute a pitch. Now, he really thinks, ‘All right, I’m in control, I’m gonna go after people.’ That’s definitely a sign of growth. It’s a sign of maturity. It’s a sign of a young player coming into himself. I’m really proud of him for that. It takes mental fortitude to get there and I think we’ve really seen him grow that way this year.”

Where in the past he allowed a bad pitch to turn into a bad inning and a bad outing, Keller pitched with more confidence and conviction and learned how to escape jams.

“Being able to slow the game down has been a huge thing for me,” Keller said. “In the past, when I’d get runners on base I’d get a little flustered and keep thinking about the previous at-bats instead of slowing it down and thinking about the next situation and the next pitch. I think that’s been huge for me, to have success and keep going and to have the outings that I’ve had. To be able to take a deep breath, take a step back and slow things down is really helping me out.”

Keller was voted the winner of the Steve Blass Award as the team’s top pitcher by members of the BBWAA.

Mitch Keller, Filthy Breaking Balls. ???? pic.twitter.com/ctoyNfZmBc

— Rob Friedman (@PitchingNinja) October 3, 2022

The future: Keller led Pirates pitchers in games started, innings pitched and walks, and ranked second in strikeouts.

He couldn’t wait to work on getting better.

When one pitch wasn’t working, Keller wasn’t afraid to rely on something else. He still threw his four-seamer the most (33.1%) but held opponents to a .206 batting average with his slider. No wonder Keller wasn’t ready to call himself a sinkerballer just yet.

“I’m still trying to find my way. It’s definitely been a growth period for me this season, just finding who I am as a pitcher and where the game’s at and where the hitters are at,” Keller said. “My four-seamer wasn’t playing like I’d hoped it would so we needed to adjust. I think adding the sinker and adding the sweeping slider has helped me develop. It’s a new arsenal, really. To be able to use that in games and do well with it has been a huge confidence booster for me.”

Number of SLs thrown by MLB SP's this year w/:
>= 18" Horz
>= 85 MPH

Ohtani - 6
Darvish - 3
Stroman - 3

No other MLB SP had thrown more than one SL w/ those characteristics.

Mitch Keller threw SIX of those in his start last night alone. Absolutely insane. pic.twitter.com/blwbrh7M0w

— Nathaniel Plotts (@nplotts5) June 25, 2022

Keller headed into the offseason with the confidence to know that he belongs in a major league starting rotation. Where he went searching for solutions last year, he intended to make tweaks this time. He hopes to develop into an anchor and finally live up to his top-prospect status.

“I can really get to work on some other things rather than just trying to get velo back and trying to throw hard,” Keller said. “I feel like I can be the guy. I’m not going to put that on myself or anything like that. It just comes naturally to a clubhouse and to a team. I feel confident in my abilities.”