BALTIMORE – Orioles right-hander Daniel Cabrera is feeling discomfort in his forearm, and although an MRI showed no damage, Baltimore manager Dave Trembley is considering moving back the struggling pitcher in the starting rotation.

Cabrera's fastball lacked its usual velocity in a lackluster performance Sunday against the New York Yankees. He was examined by the team orthopedist Monday and received an MRI on his right arm Tuesday.

Trembley said Wednesday that the MRI came back clean, but Cabrera still may miss his scheduled to start against Tampa Bay on Saturday.

“We're going to wait to see what I'm going to do. I might have to give him an extra day,” Trembley said. “He hasn't played catch in a couple days.”

Trembley won't make a decision until the pitcher again, either Thursday or Friday.

“I can't say when he's going to pitch, or if in fact he's not going to pitch, until he plays catch,” Trembley said.

Cabrera gave up seven runs in 3 2-3 innings Sunday, the fifth time in eight starts since the All-Star break he has surrendered at least six runs. His ERA has soared from 4.33 to 5.24 in that span.

Also, the Orioles activated right-hander Greg Aquino from the disabled list Wednesday – and then promptly designated him for assignment.

The 30-year-old Aquino had a 12.54 ERA in nine games with Baltimore before a hamstring strain forced him onto the DL on July 13.

Aquino was claimed off waivers from the Milwaukee Brewers in December 2007.