Dedniel Nunez returns to IL after brief Mets comeback

PHOENIX — Dedniel Nunez’s anticipated return to bolster the Mets’ bullpen lasted only one appearance.

The rookie right-hander returned to the injured list Thursday with forearm tightness, a day after he was unavailable to pitch in relief against the Diamondbacks.

Nunez pitched 1 ²/₃ scoreless innings with three strikeouts Saturday against the Padres in his return from the IL but said he felt discomfort in the forearm after returning to the team hotel.

He had difficulty getting loose after the Mets arrived in Arizona earlier this week, and during a pregame throwing session Thursday, he said he had discomfort while utilizing his breaking pitches.

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Nunez was scheduled to return to New York following the Mets’ 3-2 victory over the Diamondbacks and is expected to receive an MRI exam.

In a spot Nunez might have otherwise been used Wednesday, manager Carlos Mendoza turned to Phil Maton, with the Mets ahead by one run in the eighth inning.

Maton walked the leadoff batter then got two outs before Edwin Diaz was summoned for the four-out save.

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But Diaz imploded in a second straight appearance, walking two batters in the eighth before Corbin Carroll smashed a go-ahead grand slam.

Nunez has pitched to a 2.31 ERA in 25 appearances this season, emerging as a key setup option for Mendoza.

The Mets have also used Jose Butto in some of the highest-leverage spots.

“It’s a little frustrating [to go on the IL] after you were able to come back and get that adrenaline and be able to do your job,” Nunez said through an interpreter. “But it’s also part of the process.”

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It was Nunez’s arm soreness that led to an IL stint beginning late last month that in part played a role in the Mets trading for Ryne Stanek and Huascar Brazoban before the trade deadline.

The Mets at the time also had Reed Garrett and Sean Reid-Foley on the IL. Reid-Foley has not yet returned and may be finished for the season.

The Mets did not make a corresponding roster move for Nunez’s latest placement on the IL but will return to 26 players Friday, when Tylor Megill is recalled from Triple-A Syracuse to pitch against the White Sox.

Further bullpen help will arrive by Sunday, when rosters expand to 28 players.

“[Nunez] is a big loss, but guys will step up,” Mendoza said. “We have done it the whole year, and guys will continue to get opportunities, and guys will come up, and the guys that we have got in that room will continue to get huge outs.”

The Mets improved to 35-31 on the road this season. They are 35-33 at home.

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