Megill (shoulder) struck out the side after entering in relief during a rehab outing with Double-A Binghamton on Thursday, Anthony DiComo of MLB.com reports.
The Mets are set to have a fully healthy rotation shortly, as Carlos Carrasco (oblique) is likely to return during the team's weekend series against the Nationals. That leaves Megill without a spot in the starting five, though he could pitch in high-leverage situations out of the big-league bullpen once activated.