Phillies believe new reliever Brad Keller is ‘one of the best in the business’

It’s not unusual for a pitcher’s velocity to increase a little after transitioning from starting to relieving. But when Brad Keller moved to the Chicago Cubs bullpen last season, his fastball jumped over 3 miles per hour.

The increased zing — an average of 93.7 mph in 2024 became 97.1 mph last year — was followed by a career season. Keller posted a 2.07 ERA and 0.962 WHIP in 69⅔ innings with the Cubs, primarily pitching in a setup role. And he parlayed that into a two-year, $22 million contract with the Phillies last week.

“There’s nothing like the adrenaline spike when the phone rings and your name’s called,” Keller said on Monday. “So I really grew into that.”

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Behind closer Jhoan Duran, Keller is set to become one of the Phillies’ top right-handed relief options along with Orion Kerkering. The Phillies also added righty Jonathan Bowlan to the mix last week in a trade for Matt Strahm. Another righty in competition for a bullpen spot will be Zach Pop, whom the Phillies signed to a major league deal on Monday. Pop, 29, has a 4.88 ERA in 162⅓ career innings, and spent most of last season in triple A in the Mariners and Mets organizations.

“We love Keller. We think he’s one of the best in the business, the way he stepped up last year as a reliever with the Cubs,” Phillies president of baseball operations Dave Dombrowski said. “So we really like the way the bullpen now shapes up.”

It wasn’t just the move to the bullpen that led to Keller’s velocity increase last year. He also made some key mechanical adjustments, focusing on using his lower body more. And most important, Keller felt completely healthy.

The right-hander had thoracic outlet decompression surgery during the 2023 offseason, a procedure that Phillies ace Zack Wheeler also underwent on Sept. 23. Before his diagnosis with thoracic outlet syndrome, Keller’s hand would swell up so much because of the lack of blood flow that he couldn’t grip a baseball.

Keller returned to the mound in the spring of 2024 after signing with the Chicago White Sox. He said he didn’t quite feel like himself until the All-Star break.

“Granted, I kind of rushed my rehab because I had surgery in the offseason,” he said. “And I was a free agent that year, and I really tried to be with the team and finish rehab with the team, and then kind of roll through there.”

Keller was designated for assignment by the White Sox in May 2024 and spent the rest of that season in the Red Sox organization.

“I just carried that second half into last year, where it’s like, ‘All right, that’s in the rearview. I feel good. I don’t have to worry about that stuff anymore,’” Keller said.

When Keller signed with the Cubs last January, it was to be a starter. But after the deal came together late in the offseason, and the Cubs underwent an accelerated spring training before the Tokyo Series, he wasn’t fully built up. Chicago tried him out in the bullpen. And not only did Keller find success there, he also enjoyed the new role.

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The Phillies believe the 97-mph version of Keller is here to stay.

“All of our scouting work, our analytical work, our pitching people that have taken a look at him, between [pitching coach] Caleb [Cotham] and the rest of the group,” Dombrowski said, “people that we’ve talked to feel like, ‘OK, this is him now.’ I mean, he’s a legit back-end-type guy.”

Keller still has a starter’s arsenal, using a five-pitch mix of four-seam, sinker, slider, changeup, and sweeper, which he introduced last season. He and Cotham have already discussed ways he could improve the newest offering.

“He thinks very similar to how I think about things,” said Keller, 30. “And he brought up some ideas of things that we feel like would be fun things to try, like throwing sweepers to lefties, changeups to righties, things like that that’s kind of a little unorthodox.”

This winter, other teams inquired about Keller’s willingness to return to a starting role. He said he was open to it, but he had more fun coming out of the bullpen.

Most fun of all, though, was experiencing the playoffs for the first time in his career. Keller had a 1.59 ERA in five postseason appearances with the Cubs in 2025, recording two saves and one hold. One of his biggest priorities in free agency this winter was joining a contender.

“Once you get a taste of that,” Keller said, “that’s what you crave every single year.”