The Mets now have until Tuesday afternoon to work out a deal with the Red Sox, who apparently are willing to assume the $2.7 million remaining on Wagner's contract this season.
Wagner, who spent the last 11 months recovering from Tommy John surgery, returned to the mound on Thursday night for the first time since Aug. 2, 2008. He pitched a scoreless eighth inning, striking out two of the three hitters and unleashing a fastball that touched 96 mph.
"I thought he was very good, outstanding life, even in that short appearance," Mets manager Jerry Manuel told
The former Mets closer has a no-trade clause attached to his four-year, $43 million deal, but he has expressed that he would not block a trade to a contender.
The six-time All-Star has piled up 385 saves throughout his career to go along with a sparkling 2.40 ERA.
Wagner was taken by the Astros with the 12th overall pick in the 1993 First-Year Player Draft and spent his first eight seasons in Houston, establishing himself as one of the game's premier closers. Prior to the 2004 campaign, Wagner was traded to the Phillies in a cost-cutting move that netted Houston Brandon Duckworth, Taylor Buchholz and Ezequiel Astacio. Wagner signed his current four-year deal with the Mets before the 2006 season.