The AL Central leaders made the move Wednesday. They also moved left-hander Ron Mahay from the 15-day disabled list to the 60-day DL to make room for Flores on the 40-man roster. Mahay injured his right shoulder last weekend when he stumbled off the mound to field a grounder.
Mahay's injury left the Twins with just one healthy lefty in the bullpen in middle man Glen Perkins.
Flores is 2-0 with a 2.96 ERA in 27 1-3 innings for the Rockies this season. Opponents are hitting just .224 off of him, but he has allowed 22 hits and 13 walks in 47 appearances.