The Philadelphia Phillies roster has a major hole to fill after losing setup man Brad Keller to a season-ending injury, opening the door for an unheralded arm to step into high-leverage opportunities.
Interim manager Don Mattingly told reporters, including Matt Gelb of The Athletic, that right-hander Jonathan Bowlan could move into a more important role with Keller sidelined.
“His stuff has been good and he’s performing,” Mattingly said. “Bullpens, you always go into the season with some idea who’s your ninth-inning guy, who are your setup guys and things like that. But, for me, bullpens always set themselves because the guys that are pitching well get the ball.”
Bowlan joined the Phillies this season in a trade that sent reliever Matt Strahm to the Kansas City Royals. The righty has delivered a 2.84 ERA across 34 appearances. He hasn’t typically worked in the later innings, but has received more chances in big spots recently. Bowlan came into July with two holds on the season. He’s already picked up three holds this month.
“Who’s throwing the ball the best gets the ball the most,” Mattingly said, relayed by Gelb. “That’s just the way it works, and that’s what he’s been doing.”
Philadelphia Phillies Roster Update: Jonathan Bowlan To Get More Opportunities After Brad Keller’s Injury
GettyPHILADELPHIA, PENNSYLVANIA – JUNE 15: Jonathan Bowlan #52 of the Philadelphia Phillies reacts in the eighth inning against the Miami Marlins at Citizens Bank Park on June 15, 2026 in Philadelphia, Pennsylvania. The Phillies defeated the Marlins 7-0. (Photo by Mitchell Leff/Getty Images)
Bowlan was sparsely used over his first two big-league seasons, totaling just three appearances across 2023 and 2024. He was a more regular member of Kansas City’s bullpen last season. Bowlan tossed 44.1 innings with a 3.86 ERA for the Royals in 2025. The club chose to swap him out for Strahm, who was more expensive but came with more late-inning experience.
With the Phillies, Bowlan has increased his fastball velocity by nearly 2 mph. He’s posted a 29.7% strikeout rate, easily his best mark in the majors. Bowlan has also trimmed his walk rate to 6.3%. Free passes had been a problem during his time with the Royals. The underlying numbers support Bowlan’s strong performance. He has a 2.81 xFIP and a 2.59 SIERA. Bowlan has allowed a .308 batting average on balls in play, right in line with his career norm.
Will the Phillies Trade for a Reliever?
The Phillies made one of the biggest splashes of the 2025 trade deadline, sending Eduardo Tait and Mick Abel to the Minnesota Twins in exchange for Jhoan Duran. The big righty solidified a closer position that had been unsettled for multiple years in Philadelphia. Duran has already saved 24 games this season. The club has Orion Kerkering and Jose Alvarado working the later innings before handing the ball to Duran.
Despite some well-known names in the late-inning mix, the Phillies rank 21st in bullpen ERA. The club could use more depth in the unit. Bowlan’s emergence will help cover for the loss of Keller, but president of baseball operations Dave Dombrowski will likely be shopping for more relief arms heading into the August 3 trade deadline.
New Phillies Reliever Poised for Bigger Role After Brad Keller Injury