Stewart is absent from the lineup for Wednesday's game against the Giants, Tim Healey of Newsday reports.
Southpaw Blake Snell is on the hill for the Giants, so the left-handed-hitting Stewart will begin Wednesday's game on the bench. Starling Marte will serve as the Mets' designated hitter in Stewart's stead, and with J.D. Martinez potentially set to report to the big club this weekend, Stewart's time as New York's primary DH may have already come to an end.