HOUSTON -- Lance Berkman's time on the disabled list will likely extend beyond Friday's 15-day mark.
Berkman has been sidelined with a strained calf muscle.
"This morning it was pretty sore," Berkman said before Tuesday night's game against San Francisco. "I did more [Monday] than I had been doing. I hadn't run on it at all since I hurt it."
Berkman did more jogging than any real running.
"I don't think so," Astros manager Cecil Cooper said of Berkman being activated in time for Friday's home game with Milwaukee. "I'm not too optimistic. I'd love to have him."
Berkman, who started slowly at the plate this year, is hitting .273 with 18 homers and 55 RBIs.
Berkman took batting practice Tuesday, but did not do any more running.
"That leads me to believe he's not as good as he would like to be," Cooper said. "You've got to make sure [with a calf injury]."
Berkman wasn't concerned about losing his timing at the plate.
"My swing feels fine," he said. "We're into August now. If you can't hit in August, you can't hit."
Gene Duffey is a contributor to MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.