KANSAS CITY -- Come Monday, the Orioles' roster could look significantly different.

Manager Dave Trembley said that he would consider moving to a four-man pitching rotation and bringing up another hitter, depending on what happens Friday night and the rest of the weekend. The Orioles could afford to use just four starting pitchers, because, after the Kansas City series, the team has three off-days and only five games in the next eight days.

"As we get closer to the weekend," Trembley said, "those things will be clarified."

Trembley didn't specify the pitcher that might be removed from the 25-man roster, but Steve Trachsel has been struggling recently. Entering Friday's game, he hadn't made it longer than three innings in three of his last four starts and had a 7.48 ERA, the worst of the five starters. Daniel Cabrera, Brian Burres, Jeremy Guthrie and Garrett Olson are the Orioles' other starters. They all have ERAs of 4.32 or better.

If Baltimore does shorten its rotation, a hitter will most likely join the team. One of the main candidates, Trembley said, is Oscar Salazar, who had an impressive Spring Training and is hitting .306 at Triple-A Norfolk. Luis Terrero is another possibility. He's hitting .360 for Norfolk.

Although it's unclear what the rotation will look like in the next couple of weeks, Trembley knows that injured starter Adam Loewen won't be ready. Loewen aggravated his surgically-repaired left elbow in late April and has been on the disabled list since. He still isn't pitching from a mound, but is doing strength exercises. Trembley doesn't know when Loewen will be able to start pitching from a mound, but said he'd have to pitch at extended Spring Training before he'd be ready again for the Major Leagues.

"I think we pretty much know what we want to do," Trembley said, "but we're going to wait."