Jayson Werth had to be removed from Tuesday night's game in the ninth inning with an injury to his hip or groin area, leaving the Nationals outfielder's status for Wednesday uncertain.
Werth believes he hurt himself tracking down Arizona pitcher Ian Kennedy's fifth-inning single to right. He remained in the game until the ninth inning, when Brian Bixler replaced him in right field.
"It could just be like a muscle spasm," Werth said. "We'll see how it feels tomorrow. It's real mild. I don't think it should be a big deal."
The Nationals gave conflicting information on the precise nature of the injury. Manager Davey Johnson initially said Werth "tweaked his hip." A club spokesman then told reporters the injury was actually to Werth's groin. The right fielder later referred to it both as a "hip flexor" and then as a groin injury.
Werth has started 121 of the Nationals' 127 games this season, missing two games in San Francisco in June with a sprained ankle.
"I feel like I've been pretty fortunate to get through the season," he said. "I've kind of stayed away from some things. I sprained my ankle in San Fran, missed a couple days. But you get dinged up. That's just part of it. I don't think it's anything that should keep me out too long."