Peters was optioned to Triple-A Salt Lake on Tuesday.
Peters delivered five scoreless frames in Sunday's spot start, but he nonetheless makes his way back to the minors. The 26-year-old has a 2.63 ERA, 1.39 WHIP and 12:5 K:BB over 13.2 major-league innings this season and should be in consideration when the Angels require an additional starter in the future.