On Dedniel Núñez’s spring training debut

“Really good. First time out and he’s already touching 98 [mph], 96, 97 consistently,” the Mets’ skipper said. “Slider was good. Same guy we saw last year when he was healthy. Another good sign there.”

The right-hander needed just 11 pitches for a 1-2-3 inning, with eight going for strikes, including three called strikes and one whiff. He averaged 88.9 mph on six sliders, which was up from 87.5 mph average last year.

With Opening Day coming up in under two weeks, Mendoza said they are going to be careful with overworking Núñez, but they have to give him a couple more outings to get him ready to start the season.

“We just got to make sure he’s feeling good to go when we break camp and that we feel comfortable with him breaking camp with us,” Mendoza said. “We’ll see what happens in the next few days.”

On Mets’ eighth-inning bullpen plans

Núñez became a big piece of the bullpen for the Mets last campaign — posting a 2.31 ERA and 0.914 WHIP in 35 innings over 25 outings in his debut season in the big leagues — and was a big loss when a strained flexor tendon in his right arm kept him out of the postseason.

“We felt it, we felt it when we didn’t have him, because he was a huge part of that bullpen pitching [in] high-leverage [situations],” Mendoza said. “It was, I’m not gonna say easier, but knowing that you had him available, piecing it together it gave us another weapon there to get to [Edwin] Diaz in the ninth.

“And then when he went down, some of the guys step up, but it was a big difference there.”

The 28-year-old Núñez will be a candidate for that role in the eighth this year, but Mendoza has lots of options at his disposal.

“We got a few options,” the skipper said about the final guy to bridge the gap to sounding the trumpets. “That’s what makes our bullpen part of our strength of our team.

“When you’re talking about whether it’s Núñez healthy, [A.J.] Minter healthy, [Ryne] Stanek, Reed Garrett. There’s a lot of options there. We just gotta keep them healthy.”

New York pitchers led MLB with 214 strikeouts in late and close situations but pitched to a 1.26 WHIP (136 hits and 79 walks) in 170.1 innings in that scenario (16th in baseball) with a .222 opponent batting average (12th).

On José Butto running around

Butto, who had been dealing with a “minor” groin injury returned to the mound to pitch a scoreless inning on Monday.

And, of course, the right-hander on two occasions had to run to cover first base causing the manager’s heart to skip a beat.

“A hundred percent,” Mendoza said when asked about the heart-in-mouth moment, adding he turned to assistant pitching coach Desi Druschel to say, “Of course, this is gonna happen [today] a guy was dealing with a minor [injury] and then he’s got to cover first base twice.”

“I’m glad he checked that box,” he said of Butto moving around the field. “And I checked with him after that inning and he said he was feeling good.”

Butto allowed one hit and got a strikeout, throwing 14 pitches (nine strikes) and getting three whiffs on seven swings with two called strikes. He averaged 94.6 mph on seven fastballs

On Brandon Nimmo’s return to the outfield

Nimmo, who has been dealing with a knee injury got the start Monday in left field for his first action in the outfield since Feb. 28. With the Mets having an off day on Tuesday there won’t be a chance for the 31-year-old to play consecutive days in the outfield, but that’s not something the skipper needs to see before Opening Day.

“I don’t think I need to see it,” Mendoza said after shaking his head and shrugging. “He’s going to continue to play, he’s gonna continue to get some time off when he needs to. And I think today was a good step.

“Off day tomorrow, back at it on Wednesday.”

Nimmo told SNY’s Michelle Margaux his knee is “doing well” and he is “really happy to get back to this spot.”

“Was a little iffy there for a week and wasn’t sure if I would be able to get back out there,” he told Margaux. “Felt really good the last few days and today it felt great so I’m really happy to be back in the field.”

The outfielder added later that they “pushed a little bit more” to be able to play in the day’s game and the knee is “making really good progress and I’m very happy with the last three days.”

“We’ll see how it reacts tomorrow,” he continued. “… We’re kind of getting down to the end here and decisions need to be made on playing the field and DHing and all that.”

There wasn’t too much action out there for him — especially as Griffin Canning retired nine Rays via the strikeout — but Nimmo was glad to be out there as “that’s part of getting back out there… just the time on the feet and in the cleats and ramping up for the at-bats.”

“I’m just gonna try and get as much as I can,” Nimmo said about the number of at-bats he’s looking to get in the final week to get back on track. “Whether it’s backfield at-bats or whether it’s in the game, I’m gonna try and get three or four every day to try and start treating it a little more normal.”

He added he is “optimistic” that the injury is on the “downhill side of this” and once the knee quiets down he won’t have to deal with this injury during the year.

“Good timing for Opening Day,” Nimmo said, “but I do think that its something that we should be able to put in our rearview mirror once it’s taken care of.”