To make room on their roster for Bay, the Mets designated infielder Omar Quintanilla for assignment.
Bay had been out of action for the past month after suffering a concussion colliding with the outfield wall during an attempted catch.
Prior to rejoining the Mets, Bay played in eight minor league rehab games; five with New York’s High-A club and three with their Triple-A affiliate. Over his eight games and 25 at-bats, the 33-year-old collected five hits, all singles, and one RBI.
Before hitting the DL, Bay had only maintained a line of .187/.253/.373 with two doubles, four home runs and six RBIs over his 75 at-bats.
Quintanilla, 30, has appeared in 29 games for the Mets this season, posting an OPS of .721 over his 70 at-bats.