Flores was claimed off waivers by the Rockies on Thursday and was optioned to Triple-A Albuquerque.
Flores made a single relief appearance for the Cardinals back in early May, allowing a run on a hit and two walks while failing to record an out. He recorded an unimpressive 5.74 ERA and 1.86 WHIP in five starts and three relief appearances for Triple-A Memphis before being designated for assignment Tuesday. He'll serve as organizational depth for the Rockies for now.