Blach had his contract selected by the Rockies on Monday.
Blach was in camp as a non-roster invitee and earned a spot on the Opening Day roster. The veteran left-hander sat out the past two years while recovery from Tommy John surgery, and he had a 12.00 ERA, 2.33 WHIP and 20:17 K:BB over 27 frames in his last big-league action during 2019.