McGuire was called back up from Triple-A Salt Lake on Wednesday, Fabian Ardaya of The Athletic reports.
Jeff Fletcher of the Southern California News Group reported that the Angels' starter for Thursday's game is now TBA, which could imply that Tyler Skaggs -- who was scheduled to take the mound -- will no longer be able to pitch. If that's the case, McGuire will likely rejoin the rotation after making a spot start against the Orioles on Sunday.