The Mets placed Megill on the 15-day injured list Monday with a right shoulder strain.
Megill was diagnosed with the injury after he was forced out following four innings in his first start of the season in Sunday's loss to the Brewers. A precise timeline for Megill's return hasn't yet been established, but given that his injury is being labeled as a strain rather than soreness, he appears likely to miss more than the minimum 15 days. The Mets recalled Reed Garrett from Triple-A Syracuse to give the team a fresh relief arm in the short term, but the team will need to find a replacement when Megill's next turn through the rotation comes up this weekend in Cincinnati.