Mets first baseman Dominic Smith looks on against the Phillies...

Mets first baseman Dominic Smith looks on against the Phillies at Citi Field on Sept. 6, 2017. Credit: Corey Sipkin

PORT ST. LUCIE, Fla. — Dominic Smith learned a hard lesson under new Mets manager Mickey Callaway on Friday. Show up late, take a seat.

Smith, who knew Thursday afternoon that he was penciled in to start Friday’s Grapefruit League opener, didn’t get to the clubhouse in time for the 8:45 a.m. pregame meeting. As a result, Callaway took down the original lineup card and replaced Smith with Peter Alonso, the first base prospect from Double-A Binghamton. Then Smith had to explain himself.

Callaway’s debut at First Data Field was a win-win. While the 6-2 victory over the Braves was largely inconsequential — aside from a solid two-strikeout inning from Zack Wheeler — Callaway got to assert his authority and make an example of Smith, who spent the afternoon watching from the dugout bench. “I think that we have expectations for guys,” Callaway said. “If they don’t meet that expectation, we have to hold them accountable.”

When asked about it by reporters, Smith, 22, initially didn’t reveal the reason for his benching. A few minutes later, he was called into the manager’s office, and after a five-minute chat, he returned to his locker, where he was counseled by two Mets media relations personnel. Moments later, reporters were waved back over and Smith copped to the offense.

“Not that late, but late enough for it to be a problem for sure,” he said. “I shouldn’t be cutting it close like that. I’m a professional. This is my job. This is my career. It’s my livelihood. I felt like I definitely did let them down today.”

With the Mets having signed Adrian Gonzalez during the offseason, Smith already is ticketed for Triple-A Las Vegas, and he didn’t help his cause by blowing his first opportunity to start. He had earned plenty of positive attention for his offseason weight loss, but this was not the way to kick off what already is an uphill battle to get to the big leagues.

“It’s a little shocking,” Callaway said. “He’s trying to win a job. It’s unfortunate.”

Callaway wouldn’t say whether Smith will be in the lineup against the Cardinals on Saturday, but he sounded confident that he won’t be late.

When asked how many times he has used the word “accountable” in his conversations with players, he replied, “Thousands.”

As for where being on time ranks on his list of managerial priorities, he smiled. “It’s the first thing that we said in our meeting about our expectations,” Callaway said.

He also thought the rest of the team understood what happened without him needing to address the larger group. “They knew who was supposed to play and who wasn’t,” he said.

The Smith affair was Callaway’s first disciplinary test as a manager, and a few hours into his debut as the man in charge, he was quick to lay down the law. The other Mets took notice and applauded the move.

“He’s a young guy, and he’s still trying to understand the game, but you can’t really have that kind of stuff,” Todd Frazier said of Smith. “You’d rather be overly early than five minutes late. It’s one of those things where you live and learn. He knows he made a big mistake and it won’t happen again.”

The conversation with Callaway may have been brief, but Smith emerged repentant and pledged never to be late again. “He actually was pretty fair,” he said. “He asked me what I thought the decision should be and I agreed with him. That’s the only way it should be. They shouldn’t give me a pass or whatever. They shouldn’t give anybody a pass. And that’s what he’s been preaching since Day 1 — accountability. You got to be accountable for yourself, your actions.

“That’s the only way the team will be great and this is one of those things where I got to hold myself accountable for. To really own up to and let everybody know something that won’t be an issue or problem going forward.”

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