Pirates Announce Mitch Keller Replacement in Starting Rotation

He struggled massively after a strong first eight starts, posting a 2-7 record in his final 14 starts, a 6.95 ERA over 68.2 innings pitched, giving up 13 home runs and 53 earned runs and posting 54 strikeouts to 28 walks.

Keller struggled massively in his last start vs. the Cincinnati Reds at Great American Ball Park on Aug. 2, allowing seven earned runs and two home runs over just two innings in the 10-2 defeat.

His velocity dropped massively this season down to a career-low 93.3 mph, after generally being around the 94-95 mph range and it was clear that something was bothering him, which the Pirates found out was a serious arm injury.

The Pirates didn't add a starting pitcher at the deadline, bolstering their bullpen instead, so Mlodzinski is the pitcher they've chosen to fill Keller's role, at least for this start.

What Mlodzinski Brings to Pirates Starting Rotation

Mlodzinski started out this season in the starting rotation and spent two months in that role, before Jared Jones came back from long-term injury in late May.

He posted a 3.76 ERA over 11 games and nine starts, with a .272 batting average allowed and a 1.42 WHIP, with 46 strikeouts to 20 walks during that time.

Mlodzinski performed much better in 2026 than he did in his first run in the rotation in 2025, when he posted a 5.67 ERA over nine starts, before the Pirates sent him down to Triple-A Indianapolis and brought him back as a relief pitcher.

He has been strong out of the bullpen for the Pirates this season, posting a 2.29 ERA since moving there, doing so over 14 appearances and 39.1 innings pitched, with 30 strikeouts to 11 walks.

Mlodzinski is the most ready of the Pirates bullpen to stay in a starting role, regularly pitching two-to-three innings in his appearances and can still likely go four-five innings when he starts again.

His splitter has been sensational this season with a +7 run value from Statcast, tied for the third-best in baseball this season, while he's also had success throwing his sweeper too.

The Pirates need some solid outings from Mlodzinski, as they are in a slump and could seriously use a win against the Mets to keep their season from losing meaning quickly.