Blach cleared waivers and was outrighted to Triple-A Albuquerque on Tuesday.
The left-hander was designated for assignment by Colorado over the weekend but will stick in the organization after passing through waivers unclaimed. Blach has made 20 appearances (12 starts) for the Rockies this season and has a 6.94 ERA, 1.70 WHIP and 36:18 K:BB in 71.1 innings.