The Rockies called up infielder Daniel Castro from Triple-A Albuquerque and optioned infielder Ryan McMahon prior to Colorado's 6:05 p.m. MT tilt against the Cubs on Tuesday. To make room on their 40-man roster, the Rockies transferred lefty Zac Rosscup to the 60-day disabled list.
Castro leaves behind a 22-game hitting streak with the Isotopes as he joins the big leagues, a refreshing sign in the wake of McMahon's struggles at the plate.
McMahon, 23, was drafted by the Rockies in the second round of the 2013 Draft.