PITTSBURGH -- After he was forced out of Saturday night's game in the eighth inning by an apparent injury to his right-groin muscle, right-hander Jeff Karstens was picked up by the Pirates' relief corps.

Shortly after the conclusion of Pittsburgh's 4-0 victory over Milwaukee, Karstens himself expressed relief.

Post-game tests were encouraging, and Karstens sounded confident of not even having to miss a pitching turn. However, he allowed that additional day-after tests will bring more clarity to the injury that arose as he was delivering his eighth pitch of the eighth inning.

"Out there on the mound, you really don't know how bad it's going to be," Karstens said. "But all the tests came back pretty good. So I don't see myself missing any time. I should be ready to go in five days."

Karstens took a five-hit shutout into the eighth inning, working to protect a 4-0 lead over Milwaukee, and had allowed a pair of singles before grabbing the right side of his pelvic area after delivering a ball to Norichika Aoki.

"I kinda felt it on the pitch to [Nyjer] Morgan [who preceded Aoki in the Brewers' batting order], then again trying to throw the changeup to Aoki," said Karstens, who conceded the soreness is in the same area of the pelvic strain that in June had protracted his rehabilitation from shoulder inflammation. "But it's nowhere near as bad. And I don't think this is actually my groin; if it was, I'd definitely be able to tell."

The Pirates' infielders and catcher Michael McKenry immediately surrounded Karstens, as manager Clint Hurdle and club trainers went to check on the pitcher.

Left-hander Tony Watson came in for Karstens, who slowly made his way off the field and into the Pirates' dugout, showered by the appreciative applause of a sellout crowd in PNC Park.