Bedard experiencing shoulder soreness
The soreness is a setback for the left-hander, who has been on the disabled list with left shoulder inflammation since July 26.
Manager Don Wakamatsu said he would undergo an MRI exam on Friday in Seattle.
Wakamatsu said the discomfort was not as severe as it had been earlier, but the club did not want to take a chance on risking further injury.
Bedard will probably need to make a rehab assignment once the shoulder is ready to pitch.
Copyright 2009 by The Associated Press
MORE MLB HEADLINES
- Police question Cubs' Castro about shooting
- Source: Kuroda leaving MLB, returning to Japan
- Uggla, Bell agree to deals with Nationals
- Caffeine free: Nats P tweets out comped java