PORT ST. LUCIE, Fla. -- In pitching coach Jeremy Hefner’s joking estimation, about 17 Mets coaches and staff members were on hand to watch Dedniel Núñez throw a bullpen session on Saturday morning at Clover Park. Yet, Hefner’s quip may not have been too far from the truth.

Manager Carlos Mendoza was among a small army gathered to evaluate Núñez, a jewel of the 2024 bullpen whose health could go a long way toward determining the 2025 group’s ceiling.

“We’ve got to keep this guy healthy,” Mendoza said earlier in the week. “He’s a big piece of that bullpen, of the back end of our bullpen, and we’re going to be careful with him.”

A year ago, Núñez was far enough off the radar that the Mets didn’t even invite him to Major League camp. He debuted in early April anyway, impressing the Mets -- and their opponents -- with his upper-90s fastball and wicked slider. By the following month, Núñez had become a bullpen cog, striking out 35 batters over 27 innings with a 2.00 ERA from May 28 through July 23.

But Núñez subsequently sprained part of the pronator mass in his right forearm, missed a month, returned to make a single appearance and landed right back on the injured list. At the time, Mets officials feared major surgery. They allowed Núñez to rest and rehab in hopes that he could avoid such a fate. While Núñez managed to do just that, he still missed the club’s postseason run, feeling remorseful as he saw Mendoza stretch other relievers to their limits.

“I would sometimes watch the situations in the games that would present themselves, and I knew that I could help the team in those situations -- but I couldn’t,” Núñez said through an interpreter. “It was frustrating. I was just uncomfortable in moments like that.”

In December, Núñez experienced what he called a “setback” -- a bout of physical discomfort that slowed his rehab and prevented him from pitching in winter ball. Yet, he felt well enough by January to throw two live BP sessions -- one at the Mets’ Dominican academy, and another at Licey, the winter ball team for which Núñez had hoped to play. Hitting 96 mph during those sessions did much to ease his mind.

“Once January came around, that’s when I started to feel a lot better,” Núñez said. “That’s when I started to turn a corner.”

Unlike many Mets pitchers, Núñez has yet to throw live batting practice at camp. His bullpen session on Saturday was his second of spring, and team officials intend to keep his progression deliberate. While their goal is to have Núñez ready for Opening Day, they do not fear a world in which he needs an extra week or two.

“In the range of outcomes, that’s definitely a part of it,” Hefner said. “It’s our hope to get him ready, and he’s on track to be ready. But we are not going to force him into something he’s not ready for.”

If healthy, Núñez profiles as one of the Mets’ seven best bullpen arms, capable of assuming a high-leverage role. Unlike many other bullpen candidates, however, Núñez has accessible Minor League options, allowing the club to start him out slowly at Triple-A Syracuse if it desires. The injured list presents another option if Núñez fails to progress as team officials hope.

Much will depend upon what unfolds over the next month. If Núñez begins facing hitters in the coming weeks, makes his way into Grapefruit League games and experiences a reasonable level of success, he would seem destined for a job in the Opening Day bullpen. If not, the Mets won’t fret, knowing he’ll be able to help eventually.

Right now, Hefner said, Núñez is “climbing.” Once he rejoins the bullpen -- be that on Opening Day, in early April or beyond -- it will be a “huge boost.”

“But we are going to listen to him and listen to his body and what his body’s telling us,” Hefner said. “We are not going to shortchange him because he’s got to be on the Opening Day roster by some arbitrary date. When he’s ready, he’s ready. That’s when we’ll insert him.”