Colorado Rockies right-hander Chase Dollander is expected to require surgery to repair UCL damage in his elbow, a major MLB injury development for the club's top young pitcher.
MLB's official transactions feed confirms Colorado transferred Dollander from the 15-day injured list to the 60-day injured list on June 12 because of a right elbow strain. MLB Trade Rumors reported that Rockies manager Warren Schaeffer told The Denver Gazette that Dollander was expected to need surgery, with one more pre-operation appointment still ahead before plans were finalized.
Dollander Move Reaches 60-Day IL
Dollander had been out since mid-May with the elbow injury. The 60-day move came as Colorado selected left-hander Sean Sullivan from Triple-A Albuquerque and optioned left-hander Sammy Peralta, two roster transactions also listed in MLB's official feed for June 12.
The wording matters because the club had not finalized the exact operation when the report was published. Schaeffer's update, as relayed by MLBTR from The Denver Gazette, moved the situation from a standard elbow strain to an expected surgical case.
If Dollander undergoes an internal brace procedure, MLBTR noted the usual return timeline is about 12 to 14 months. A full Tommy John reconstruction would carry the risk of a longer absence, potentially affecting most or all of the 2027 season.
Colorado Loses Its Highest-Ceiling Arm
The injury is especially significant for the Rockies because Dollander is one of the few pitchers in the organization with front-of-the-rotation upside. Colorado drafted him ninth overall in 2023, and he had begun to show progress in his second major league season.
MLBTR listed Dollander at a 3.89 ERA over 44 innings this season, with a strikeout rate around a quarter of the hitters he faced. The report also noted his four-seam fastball and sinker were reaching the 98-99 mph range and that he generated swinging strikes on 12% of his pitches.
Those numbers do not make a full breakout by themselves, but they explain why the injury lands hard. For a team deep in a rebuild, the development path of a controllable starter matters as much as the standings.
Rockies Rotation Plans Take Another Hit
Dollander remains under club control for six seasons, barring any future service-time changes in the next collective bargaining agreement. He will receive MLB service time and salary while on the injured list, and Colorado can put him back on the 60-day IL after spring training opens next year if needed.
The Rockies already faced a difficult rotation reset. MLBTR noted that Kyle Freeland, Tomoyuki Sugano, Michael Lorenzen and Jose Quintana are all headed toward free agency, while several other arms on the 40-man roster project more as depth options.
The verified roster result is clear now: Dollander is on the 60-day injured list with a right elbow strain, and the reported expectation of UCL surgery changes Colorado's pitching outlook beyond this season.