SAN DIEGO – The Rockies rotation took another hit.

Right-hander Aaron Cook is believed to have strained a muscle in his side, which would force him on the disabled list, along with Rodrigo Lopez, who is out for the season with elbow surgery, and Jason Hirsh, who is sidelined until at least mid-September with a fractured right fibula.

Indications were that big-league veteran Elmer Dessens, recently released by Milwaukee and signed to a minor-league contract by the Rockies, will replace Cook in the rotation in Thursday’s series finale against the Padres.

Ubaldo Jimenez was promoted earlier from Triple-A Colorado Springs and started Wednesday night in place of Lopez. Left-hander Franklin Morales is scheduled to make his big-league debut in Los Angeles on Saturday in place of Hirsh.

The Rockies continue to talk with teams about pitchers who have cleared waivers, but Baltimore is now indicating that Steve Trachsel is not on the market, and the asking price for Ramon Oritz from Minnesota, Chad Guadin of Oakland and Josh Towers of Toronto has kept talks from getting serious.

The Rockies also figure to be active in placing waiver claims, including Ortiz, but not Byung-Hyun Kim, who Arizona owner Ken Kendrick said Wednesday morning will be released after making two starts for the Diamondbacks.