The Rockies reinstated Sullivan (shoulder) from the 15-day injured list and optioned him to Triple-A Albuquerque on Wednesday.
Sullivan landed on the 15-day injured list in early July due to left shoulder impingement, and he wasn't cleared to embark on a rehab assignment until Sept. 10 . There's not enough space for him in the Rockies' rotation, so he'll stick around in Triple-A, where he has a 5.71 ERA and 1.55 WHIP across 58.1 innings.