Roy Oswalt woke up with a sore back last Friday and figured he'd slept on it wrong. Unfortunately for the right-hander and his Astros teammates, the problem will require more than a quick-fix massage, and Oswalt's immediate pitching future is now in question. Minutes before the Astros were to take the field for their game with the Reds on Sunday, Oswalt was scratched from his start, citing spasms in the middle of his back that he felt while throwing his warmup pitches in the bullpen. "I threw 20 pitches to warm up for this game, and as soon as I started throwing curveballs, it just locked up," Oswalt said. "I knew there was no way I would get through another five, six, seven innings. It was time to shut it down."