Angels medical director Lewis Yocum, whose examination confirmed Rockies medical director Thomas J. Noonan's diagnosis of a complete tear of the ulnar collateral ligament, will perform the operation.
De La Rosa suffered the injury May 24 during a start against the D-backs. De La Rosa was 5-2 with a 3.51 ERA. History says the Rockies will miss him badly. They were 4-9 last year when he missed 13 starts with a finger injury.