NEW YORK — Just after 1:30 p.m. Sunday, Buck Showalter called his group of veterans into his office. It’s a group he’s relied on throughout this season, for counsel, for leadership, for accountability. It’s a group that grew smaller when the team shipped out veterans at the trade deadline and shifted course for the final two months.

On this day, the lingering members of the New York Mets’ core — Francisco Lindor, Brandon Nimmo and Pete Alonso among them — listened as Showalter delivered his news.

Sunday would be his final game as manager of the Mets. Late Saturday night, following New York’s doubleheader sweep of the Philadelphia Phillies, Showalter had been fired.

“It was one of those conversations where there was a lot of seconds with silence,” Lindor said later.

New York’s veterans had known David Stearns was coming in as a new president of baseball operations. They knew they’d been massively disappointing in 2023, falling from a 101-win campaign to one where they spent the last four months under .500. They knew change was coming to the organization, likely in a big way.

Still, the news that Showalter shared, about 90 minutes before the final first pitch of the season, took them aback. Many had hoped, privately and publicly, that the manager would be retained.

In his office, they expressed that surprise and their own guilt, that the team’s underperformance had put Showalter in this position.

“It all falls on us,” Nimmo said after the game. “I don’t really feel like Buck was the problem.”

“You guys are going to be OK,” Showalter told them in the meeting.

“He was a true professional and let us know before the world knew,” Lindor said. “I appreciate him. I love him.”

On Saturday night, after the Mets had swept a doubleheader and by the time most people within the club had left Citi Field, Mets GM Billy Eppler walked into Showalter’s office, presenting two choices: resign or be let go.

Stearns had made the decision to move on from Showalter. Once Stearns agreed to the Mets job a few weeks ago, it was clear that the Mets would be hiring a new manager. (“Once David signed, we kind of knew where it was going to go,” owner Steve Cohen said.) Anyone who knows both Stearns, a New York City native, and Showalter says that the two personalities would not have meshed well. Stearns likes to operate in a hushed way; he can be personable, but he’s not going to reveal much in casual conversation. Showalter can be chatty in a folksy way, and while he’s known to shield players and staffers from criticism, the words don’t always come out as buttoned-up as many modern baseball executives prefer. One person put it succinctly: “Very, very different personalities.”

While players may have been surprised by the timing of the news, the change shouldn’t jump out as all that unusual.

“The way it works,” Cohen said, “when you bring in a president of baseball operations, they’re entitled to bring in their own people.”

Stearns never talked to Showalter. So Eppler delivered the news to Showalter. After receiving the news, Showalter’s mind drifted back to the trade deadline, to a conversation that the manager had with Max Scherzer.

“One thing that bothered (Scherzer) the most was he felt like his teammates might think he was jumping ship,” Showalter said. “Which was obviously not the case.”

So, Showalter wouldn’t quit. He’d get fired.

“The players know I would never quit or resign,” he said.

After Showalter broke the news to the players, he appeared in front of the media for the daily pregame press conference. Once the questions stopped, he said that the Mets wanted a new manager. Uncharacteristically, Showalter read from a prepared statement. Or he at least tried to. He had jotted some notes down ahead of the press conference, not wanting to forget something. He made it through a paragraph. Maybe. Then he just freelanced from his mind.

“I was honored to get a chance to manage a second New York team,” Showalter said. “I’m proud of what the Mets did. We won close to 180 games in two years. Especially last year, as much fun as I’ve ever had in the game. It reminded me of why I always loved this kind of work.

“I wish things could have gone better this season because Mets fans deserve that. … It’s not the ending I wanted, but I still love the city and the players. … And if I talk anymore, it won’t get good.”

Showalter didn’t want emotion to get the best of him. There were some cracks in his voice.

“I left a bunch out,” he said. “But that’s about it. How’d I do?”

In Sunday’s ninth inning, with Philadelphia adding on meaningless runs in a meaningless game, Showalter made one final trip to the mound, replacing Denyi Reyes with Anthony Kay. Showalter’s gait from the dugout to the mound is always quick; Lindor noticed this time how quickly Showalter’s mind was moving. As the manager started his march back to the dugout, Lindor took a couple of strides with him and patted him on the back.

“You’re right where you need to be,” Lindor told him.

“He was in the game, but at the same time it was very tough to concentrate on the moment. And then the crowd is giving him the ovation,” Lindor said postgame. “He knows it’s his last time walking back to the dugout as a New York Met.”

Showalter had already received a large ovation from the crowd and from his team — all of them coming out of the dugout to applaud — during the exchange of lineup cards pregame. He heard it again in that ninth inning, head down on his way back into the dugout.

“It’s special,” he said after the game, his voice occasionally cracking again. “The fans were outstanding today, as always.”

“It doesn’t seem real,” Nimmo said. “He led us just a year ago to 101 wins. It’s kind of crazy that just one year later we’re saying goodbye to that relationship.”

“I was really, really upset,” Alonso said. “He does a great job of understanding his personnel — not just their talents and what they do day to day on the field, but he understands how each guy ticks on the roster as an individual. My experience playing under Buck, I feel he’s a Hall of Fame manager.”

Multiple players talked about Showalter’s ability to hold the roster together through the disappointing change in direction at the trade deadline. Other teams, especially in larger markets, have fractured under similar circumstances. A diminished version of the Mets played .500 ball over the season’s last 44 games.

“Being able to keep the group together in here can be a little more challenging (in New York) than in other places,” reliever Adam Ottavino said. “It takes some nuance and some experience, and Buck did kind of a masterclass on a lot of that stuff. I know that’s not as easy as he made it look.”

“I’ve been very proud to hold this together this year in the clubhouse,” Showalter said. “It’s been one of the bigger challenges of my career.”

“These last two months, I’ve been really proud of the guys and the way they’ve been fighting,” Nimmo said before the game and before Showalter revealed his firing. “A lot of that is Buck’s mentality of never giving up and always fighting to the end to see what happens.”

The Mets thus enter another offseason with a lengthy to-do list and a major decision to make at the top. The longest-tenured player on the team, Nimmo at one point ran down the five different managers he’s played for since 2016. Next year will be a sixth.

“That’s what these times produce,” Nimmo said. “When things aren’t going well in New York, things happen, and they happen quickly.

“It’s our job as players to try and not let these things happen again.”

(Photo of Buck Showalter and Francisco Lindor: Al Bello / Getty Images)