DENVER -- Rockies rookie left-hander Christian Friedrich is hoping his body doesn't strike midnight before the season is over.
Friedrich, 25, was originally scheduled to start Thursday against the Cardinals but was pushed to Sunday against the Giants after experiencing soreness in his back and midsection. He actually has struggled with general soreness since being hit in the right calf by a line drive on June 30. Pitching through pain caused him to alter his motion.
Friedrich said he will know he's out of the woods if he feels good during and after his bullpen session on Friday.
This season, Friedrich threw 30 innings at Triple-A Colorado Springs before beating the Padres in his Major League debut on May 9, and has thrown 84 2/3 in the Majors. In the Minors, he battled various injuries and never threw more than the 133 1/3 he logged last year at Double-A Tulsa.
"Bo [McLaughlin, a Rockies pitching coach] has been telling me they're trying to get me over the hump that's gotten to me the past couple of years," Friedrich said. "I'd get to a certain innings point, then something starts acting up. They want to try to condition my arm to get over the hump and get through that.
"If your arm hurts or your leg hurts, you can still go out there and throw, but the back is such a sensitive area I can't keep going. Hopefully this thing calms down quite a bit, so we'll see where it goes from there."
Friedrich, who gave up seven runs and six hits -- including three homers -- in 4 1/3 innings of a loss to the Reds in his last start, said he has used the extra time to strengthen core muscles that aren't always easy to work on when pitching on a normal schedule.