The Mets placed closer Bobby Parnell on the 15-day disabled list with a herniated disc in his neck. The move, made Tuesday, was retroactive to July 31.
Parnell missed the weekend series against the Royals and complained of neck stiffness. He received an epidural on Monday, but surgery hasn't been ruled out.
Parnell, 28, will be re-evaluated in "two or three days," general manager Sandy Alderson said, and if his neck doesn't respond well to the treatment, "something more significant, more invasive, would have to be considered.
"But right now we're not at that stage. Best-case scenario is he's ready to go at the end of the 15-day disabled list period."
The Mets recalled infield prospect Wilmer Flores from Triple-A Las Vegas to fill Parnell's roster spot.
The righthander last pitched on July 30, recording a save in a 4-2 win over the Marlins. This season, he has converted 22 of 26 save chances and has pitched to a 2.16 ERA in 49 games.
Manager Terry Collins said the Mets likely will go with a closer-by-committee.
"We're gonna use some different guys, mix and match a bit," Collins said before Tuesday night's game. "I don't know if we have the one guy that's 'it.' "
David Aardsma pitched the ninth inning last Friday and blew the save, but Collins said they will "continue to let Dave have a shot." LaTroy Hawkins, Gonzalez Germen and Carlos Torres also will be considered. Niese is near
Jon Niese made what is expected to his final rehab start Tuesday night with Double-A Binghamton and the lefty, who suffered a slight rotator cuff tear in late June, could rejoin the Mets Sunday. In five innings against Altoona, he allowed two earned runs, four hits and three walks, and struck out six.
"It'll depend on the outcome and how he feels the next day," Collins said, adding that if all goes well, Niese could slide into what will be a six-man rotation as they begin a series Friday night in Arizona.