The Texas Rangers placed starter Max Scherzer on the 15-day injured list due to right shoulder fatigue, according to the Associated Press (h/t ESPN).

The move was retroactive to Wednesday, while the team called up lefty Walter Pennington from Texas’ Triple-A affiliate.

Scherzer experienced issues during a start against the St. Louis Cardinals, exiting after just four innings and 68 pitches. After the game, he explained that he was “trying to grind through these starts and ramp up.”

The three-time Cy Young Award winner didn’t make his season debut until June 23 after he underwent back surgery in Dec. 2023. His recovery was also hampered by a nerve issue in his right arm.

Scherzer currently owns a 2-4 record through eight starts, posting a 3.89 ERA. The active strikeout leader in the majors has also struck out 38 batters while allowing eight walks in 39.1 innings of work.

The Rangers’ World Series defense has been off to a rough start due to injuries, as they currently sit 4.5 games behind the Houston Astros for the No. 1 spot in the AL West. Texas’ staff has been decimated by injuries, as Jon Gray was placed on the 15-day injured list due to a right groin strain on Monday.

Two-time Cy Young Award winner Jacob deGrom is scheduled to throw a bullpen session on Saturday as he recovers from elbow surgery. If he’s able to return before the end of the regular season, he should provide a boost to Texas’ rotation.

As for Scherzer, he’ll remain on the injury list until his issues with arm fatigue subside.