LOS ANGELES -- Rockies pitcher Jorge De La Rosa will undergo Tommy John surgery on his left elbow on Friday, manager Jim Tracy said Wednesday.

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.

Nelson providing Rox spark since promotion

LOS ANGELES -- Nobody expects the players recently called up from Triple-A Colorado Springs to carry the Rockies. But infielder Chris Nelson is the latest to provide a little lift.

Nelson appeared in the first two games of the series against the Dodgers and went 2-for-4, made a standout defensive play and used his speed and hustle to score one of the Rockies' two runs in Tuesday night's 8-2 loss.

Nelson doubled off Dodgers pitcher Ted Lilly to lead off the third inning, stole third and scored on pitcher Clayton Mortensen's fly ball to short right field. Nelson noticed that Dodgers second baseman Aaron Miles caught the ball and was not in position to make a strong throw to the plate.

"As a whole, we've just got to get them on base, get them over, get them in and just try to be there for each other," Nelson said.

Nelson and Eric Young Jr., who has hit .304 in five games as he attempts to show he can be the regular leadoff man, were not in the lineup Wednesday night against the Dodgers as the Rockies tried to avoid being swept. Manager Jim Tracy wanted his best defensive lineup behind pitcher Ubaldo Jimenez, so Jonathan Herrera started at second base. Also, with Ty Wigginton hot (.345, two doubles, three home runs in an eight-game hit streak), he started at third instead of Nelson.

Worth noting

• In an attempt to do something -- anything, really -- to change their momentum, the Rockies did not take batting practice before Wednesday night's game against the Dodgers. Manager Jim Tracy said hitting coach Carney Lansford suggested they skip BP, just to give players a chance to relax. But anyone who wanted to take swings in the batting cage could do so.