Roy Oswalt SP COL 8 Months

Roy Oswalt (hamstring) allowed three hits and a walk over 5 2/3 scoreless innings in a rehab start with rookie league Grand Junction Rockies on Tuesday.

He struck out a pair, throwing 41 of 55 pitches for strikes. Manager Walt Weiss indicated that how Oswalt fares Tuesday will determine what role he'll serve in for the team down the stretch. It's probably safe to say he'll rejoin the rotation next week.

Roy Oswalt SP COL 8 Months

Roy Oswalt (hamstring) will make a rehab start with the rookie league affiliate Grand Junction Rockies on Tuesday.

Oswalt has been throwing simulated games recently and has been deemed ready for a rehab start. It may be the only one he needs, as he's been amping up his pitch count lately. He should be back sometime in early September.

Roy Oswalt SP COL 8 Months

Roy Oswalt (hamstring) could make a rehab appearance this weekend.

Oswalt threw another successful simulated game Tuesday, going four innings and throwing close to 60 pitches. If he doesn't make a rehab start this weekend, he'll throw a simulated game. Either way, he's close to rejoining the Rockies' rotation. "I'm trying to get back and pitch this year and go from there," Oswalt said. "I'm hoping to come back and start at least four, maybe five games."

Roy Oswalt SP COL 8 Months

Roy Oswalt (hamstring) will throw at least one more simulated game before going out on a rehab assignment.

Oswalt is a little behind Tyler Chatwood (elbow), who also threw a simulated game Thursday. He'll throw another sim game over the weekend before likely beginning a rehab assignment sometime next week. Barring a setback, Oswalt should rejoin the rotation in early September.

Roy Oswalt SP COL 8 Months

Roy Oswalt (hamstring) threw three innings in a simulated game Thursday.

Like his teammate Tyler Chatwood (elbow), the next step calls for Oswalt to make a minor league rehab start on Sunday. However, it's unclear when he'll be activated. The veteran right-hander has been sidelined for a little over a month with a left hamstring strain.

Roy Oswalt SP COL 8 Months

Roy Oswalt (hamstring) threw 65 pitches in a bullpen session Monday.

The next step is a simulated game on Thursday. If all goes well, he could make a minor league rehab start as soon as Sunday. The veteran right-hander has been sidelined for a little over a month with a left hamstring strain.

Roy Oswalt SP COL 9 Months

Roy Oswalt (hamstring) will attempt to throw a simulated game sometime in the "near future."

Oswalt experienced a setback with his hamstring Saturday while throwing a sim game, but it was apparently minor. "I think he'll back before too long," Rockies manager Walt Weiss said. "I think he's going to move quickly."

Roy Oswalt SP COL 9 Months

Roy Oswalt experienced a setback with his hamstring Saturday while throwing a simulated game.

Oswalt made it through just two hitters before calling it quits. "It's going to take a couple more weeks," said the veteran right-hander. "I want to be out there." He has been on the 15-day disabled list since July 8.

Roy Oswalt SP COL 9 Months

Roy Oswalt (hamstring) threw a successful 36-pitch bullpen session on Tuesday afternoon.

Oswalt plans to throw a simulated game on Friday and then head out on a short minor league rehab assignment. He should be back with the Rockies by mid-August.

Roy Oswalt SP COL 9 Months

Roy Oswalt (hamstring) is scheduled to throw a 40-pitch bullpen session on Tuesday.

Oswalt said he was at about "80 percent" when he threw 15 pitches in a bullpen session Friday. Barring any setbacks on Tuesday, he should be cleared to face live hitters. Look for him to rejoin the Rockies' rotation within the next couple of weeks.