The Rockies reinstated Mears (oblique) from the 15-day injured list Saturday and optioned him to Triple-A Albuquerque.
Mears has been on the IL since May 15 with a left oblique strain. He's allowed two runs over six innings out of the big-league bullpen this season, but he will return to Triple-A where he holds a 6.97 ERA and 2.08 WHIP on the year.