Belisario is expected to be placed on the disabled list Tuesday and Wade recalled, but no move had been made before Tuesday night's game with the Mets.
Belisario, who had Tommy John elbow reconstruction and missed the entire 2005 and '06 seasons, leads the team with 43 appearances after coming out of nowhere in Spring Training to make the Opening Day roster 10 years after signing his first professional contract.
He had worked 13 2/3 consecutive scoreless innings over 12 games before giving up three runs in one-third of an inning Saturday night in San Diego.
A week earlier, Belisario was arrested on suspicion of driving under the influence.
Manager Joe Torre said Belisario told him he first felt stiffness warming up for that game, "but it didn't bother him in the game. He didn't say anything, and Sunday again it was tight, but didn't bother him, and he got on the plane and it was tight. He came in today and I saw [trainer] Stan [Conte] working on him and he came in and shook my hand."
Belisario will be examined by Dr. Neal ElAttrache and likely will have an MRI.
Torre speculated that whatever was happening with Belisario's elbow might have contributed to his shaky outing Saturday night, when he blew a save for Randy Wolf.
"It could have been," Torre said. "That's one thing I always ask the pitchers on a regular basis, how they feel. But he said, 'I'm ready.' He may have had something and didn't think of it."
Torre said James McDonald, who has shown improved command since his return from Triple-A Albuquerque on June 19, will likely emerge as Belisario's replacement as the seventh-inning pitcher leading to Ramon Troncoso and closer Jonathan Broxton.
Torre said Jeff Weaver, who won Sunday's game with three hitless innings of relief, would make the spot start Saturday in Milwaukee.
Ken Gurnick is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.