Warren was optioned to Triple-A Salt Lake on Wednesday, Jeff Fletcher of The Orange County Register reports.
Warren will head back to Triple-A on Wednesday, creating an opening on the active roster for Wednesday's starter Janson Junk. Warren has surrendered five runs on seven hits while striking out two batters over 4.2 innings in five appearances with the Angels since returning from the IL on July 12. He'll remain a candidate for a potential call-up down the road.