Montero cleared waivers Thursday and was sent outright to Triple-A Albuquerque.
Montero was DFA'd by the Rockies on Sunday after slashing .205/.267/.304 over 247 plate appearances, but he'll officially remain in the organization after passing through waivers unclaimed. Until the 25-year-old is able to turn things around at the plate, he'll serve as organizational depth in the minor leagues.