The Colorado Rockies have sent opening-day starter Jon Gray down to the minors, optioning the right-hander to Triple-A Albuquerque.

Gray was 7-7 with a 5.77 ERA over 17 starts this season, but has particularly struggled since May 13 while posting a 7.25 ERA in his last nine outings. The Rockies replaced him on the roster Saturday with outfielder Raimel Tapia, who was batting .308 with 10 home runs and 48 RBI at Albuquerque.