Marlins Option William Kempner, Recall Fresh Bullpen Arm

Despite beginning his MLB career with nine scoreless relief innings, Miami Marlins right-hander William Kempner is headed back to the minor leagues.

On Tuesday afternoon, the Marlins announced they had optioned Kempner to Triple-A Jacksonville. In a corresponding move, left-hander Dax Fulton was recalled.

We've made the following roster moves: pic.twitter.com/Xu8ch3RQNt

— Miami Marlins (@Marlins) June 16, 2026

Kempner, who turns 25 this week, made his big league debut on May 5 after tallying a whopping 34 strikeouts over 15.1 Triple-A innings to begin the season. That stint lasted just one day. But after allowing just two runs over his next 10 innings with Jacksonville, he earned another call-up on May 30 as an injury replacement for Andrew Nardi.

In six relief appearances for the Marlins this season, Kempner has allowed just three hits and two walks while striking out 10 across nine scoreless innings. The right-hander most recently pitched during Monday's 7-0 loss to the Philadelphia Phillies, tossing 2.1 hitless innings.

Since Kempner threw 33 pitches in the outing, he likely would have been unavailable for the remainder of the series. With fellow reliever Cade Gibson also unavailable after throwing 29 pitches in the eighth inning, Miami needed a fresh arm capable of providing length out of the bullpen.

Fulton, 24, previously took Kempner's roster spot after the right-hander was optioned in early May. The 6-foot-7 left-hander spent one day in the majors, allowing two runs across four innings of long relief in his big league debut before being sent back down.

A former second-round pick, Fulton has spent the majority of his professional career as a starter but will likely get another look as a bulk reliever in Miami. He has made 12 appearances (10 starts) at Triple-A Jacksonville this season, posting a 5.56 ERA and 1.56 WHIP with 46 strikeouts in 43.2 innings.

The Marlins are 36-37 on the season and red-hot in the month of June (10-3). They will aim to get back to .500 against the NL East rival Philadelphia Phillies tonight with Tyler Phillips going up against old friend Jesús Luzardo.

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This story was originally published June 16, 2026 at 4:37 PM.