Scratch Jered Weaver from Friday night's start against the Detroit Tigers.

An MRI on Wednesday revealed that the Angels' 16-game winner has tendinitis in his right shoulder. Dr. Lewis Yocum, the team orthopedist, also examined Weaver before the team announced the results of the MRI.

It's unknown if the tendinitis is related to the line drive Weaver took off his shoulder last Sunday in Seattle. Either way, he won't be available to pitch in the critical three-game series against the Tigers, who are among the contenders for a wild card in the American League.

The Angels said Weaver's next start won't be determined until this weekend, but it's likely the team will wait to see how quickly he responds to treatment before deciding when he can return to the rotation.