DENVER -- Rockies right-hander Jason Hirsh has been told that the best prescription for his ailing right shoulder is rest. But he will happily delay that for another month.

Hirsh, who has yet to pitch in the Majors this season because of a rotator cuff strain, was added to the expanded Major League roster before Tuesday night's game against the Giants.

Hirsh, who went 4-4 with a 5.80 ERA in 18 games (17 starts) at Triple-A Colorado Springs after returning to health, realizes he won't be at his best until 2009. He was never healthy and sharp enough to return to the Majors at times the club needed starting pitching.

Finally, about a month ago, through conversations involving Rockies Minor League pitching coordinator Jim Wright and head athletic trainer Keith Dugger, the club came to the realization that Hirsh won't be at his best until 2009.

"It's definitely a longer process than I was expecting, and I found out that it'll be a process that won't resolve itself until I take time off," Hirsh said. "The offseason will be a nice rest and, hopefully, a 100 percent recovery. I continued to throw and tried to find some consistency and positives.

"It's been long and frustrating. But the positives are I didn't have to have surgery, which is good. I'll have a full recovery, which is good. And I've managed to pitch decently. And I'm up here, obviously, so that's an upside."

Hirsh, 26, suffered a strain to the subscapularis muscle (one of four comprising the rotator cuff) early in Spring Training. Catcher Yorvit Torrealba tried to play through a similar injury last year, and he helped convince Hirsh to take his comeback slowly. He wanted to be a factor in the Majors sooner than this.

This is the second straight injury-plagued season for Hirsh, acquired in a December 2006 trade with the Astros.

As a rookie last year, he missed time with an ankle injury and saw his season end in August when he suffered a broken right fibula when hit by a line drive by the Brewers' J.J. Hardy. Hirsh went 5-7 with a 4.81 ERA for the Rockies last season.

The Rockies will use Hirsh in long relief, and a start hasn't been ruled out, but they'll have the opportunity to see him up close and monitor his condition.

The Rockies also have summoned right-hander Greg Reynolds, who went 2-6 with a 6.71 ERA in 11 starts earlier this season. Reynolds was the club's top pick in 2006. Reynolds has yet to be activated, however.

The club decided not to call up left-hander Franklin Morales, who went 3-2 with a 3.43 ERA during last year's playoff run but was 1-2 with a 6.39 ERA and serious control problems before being sent down to Colorado Springs. The Rockies determined that sporadic bullpen appearances would not be best for him, and they plan to have him in an instructional program.