Peralta left Thursday's start against the Giants with right shoulder fatigue, Sophia Minnaert of Bally Sports Wisconsin reports.
There is no timeline for when Peralta might return to the rotation, but given that he missed 10 weeks with a shoulder strain and had this start pushed back a few days due to shoulder soreness, he will likely head for tests. Peralta struck out three and walked two over two scoreless innings Thursday before exiting with the injury.