Peralta was recalled from Triple-A Colorado Springs on Sunday.
Peralta was roughed up in his last start Aug. 30 and sent to Triple-A, but he returns to the Brewers after the minimum 10 days in the minors. The 22-year-old won't make another start this season -- barring unforeseen circumstances -- but will be available out of the bullpen. Peralta had a 4.40 ERA, 1.15 WHIP and 91:39 K:BB over 73.2 innings as a starter for Milwaukee this season.