The Mets placed Nunez on the 15-day injured list Thursday due to right forearm tightness, Will Sammon of The Athletic reports.
Nunez just returned from a forearm issue last Friday and is now headed back to the IL following a recurrence of the injury. He missed nearly a month of action the first time around, but it's not clear how long this stint might last. It's a blow to the Mets' bullpen, as Nunez has been excellent this season with a 2.31 ERA, 0.91 WHIP and 48:8 K:BB over 35 frames.