Phillies’ Brad Keller found success as a reliever, but embraces starters’ arsenal

CLEARWATER, Fla. — Brad Keller’s transformation into a high-leverage reliever did not come with the usual downsizing of weapons. While many bullpen specialists trim their pitch mix to two or three offerings, the 30-year-old right-hander arrives at Phillies camp intent on keeping all five pitches—fastball, slider, sweeper, changeup and sinker—that carried him through eight major-league seasons and a breakthrough 2025 campaign with the Chicago Cubs.

“I do think it’s important in the big leagues, all things equal, to have more options,” pitching coach Caleb Cotham said. “You don’t have to throw two or three pitches to simplify the plan. He can keep the plan for each pitch singular in some ways, and it’s more, ‘What pitch should I throw?’ and the ability to be random.”

That philosophy helped Keller land a two-year, $22 million deal in mid-December, the marquee external move of Philadelphia’s offseason. After signing shortly before spring training in each of the past two years, the timing allowed Keller a normal winter routine and an early entry into the club’s pitching lab. His first two bullpen sessions in Clearwater have already centered on fine-tuning rather than overhauls.

Chief among the tweaks is the sweeper, a pitch added in 2023 that evolved into Keller’s most lethal weapon last season. Thrown 14 percent of the time, it produced a 45.8 percent whiff rate and a 55.6 percent strikeout rate, both career-bests for any of his offerings. Yet Keller admits he “let it rip” too often down the stretch, causing the pitch to lose shape and finish out of the zone. Opponents went hitless against it in June but slugged .571 in September, albeit on only one home run in 16 pitches.

“Really, it’s helping him capture the zone with that pitch as much as possible, especially when it’s moving how it’s moving,” Cotham said. The staff’s early focus is nudging Keller toward more back-door locations to left-handed hitters while maintaining the horizontal break that averaged 15 inches in April and September.

The changeup—used sparingly at 12 percent overall but 25 percent against lefties—represents another spring project. Keller calls the pitch “a little haywire” when his grip or cue drifts, and the coaching staff wants to stabilize its release to keep opponents under the .189 batting average it yielded last year.

Mechanical adjustments and a velocity spike—Keller’s fastball jumped from 93.8 mph in 2024 to 97.2 mph in 2025—helped him thrive in late innings for the Cubs. He believes the deep repertoire prevents hitters from sitting on any one look.

“If you’re a two-pitch or three-pitch pitcher, and you don’t have your best pitch, it can become predictable,” Keller said.

Cotham sees a pitcher whose experience as a starter gives the Phillies flexibility to treat him almost like a rotation member in terms of preparation, even though Keller’s role will strictly come in high-leverage relief. On Friday he threw alongside Trevor Richards, Chase Shugart and Tim Mayza, another sign that the club expects Keller to anchor the back end without stripping down the arsenal that got him there.

After years of bouncing between organizations, Keller has found both a home and a philosophy in Philadelphia: more pitches, more problems—for opposing hitters.