PHILADELPHIA -- The Mets’ bullpen, a source of resilience throughout this season, will need to recover from yet another loss.

Right-hander Dedniel Núñez is done for the season due to a strained flexor tendon in his right arm. Núñez received a platelet-rich plasma injection in the tendon and hopes to avoid surgery, but the Mets won’t know how viable that might be until his body has time to respond to the PRP shot.

“Everything is on the table, but right now, we thought that was the best route to go with the injection here,” manager Carlos Mendoza said. “Hopefully that works, and then we don’t have to worry about surgery. But, too early to tell.”

Núñez had been a revelation for the Mets in the middle of the season, producing a 2.00 ERA with 35 strikeouts over 27 innings from May 28 through July 23. But he went on the injured list shortly thereafter with a right pronator strain, spent a month there, then returned for a single appearance on Aug. 24.

Afterward, Núñez complained to team officials that he wasn’t responding well from his throwing sessions, prompting another examination and trip to the IL. He subsequently went for a second opinion, which confirmed what president of baseball operations David Stearns referred to as a “strain” of the tendon. A PRP shot was the recommended treatment.

“Disappointing,” Mendoza said. “He’s been huge for us, and we had hopes that we were going to get him back, and that’s not the case.”

With Núñez done for the year, the Mets will continue to rely on a mix of Phil Maton, Reed Garrett, Danny Young, José Buttó and others to set up closer Edwin Díaz.