The Mets are taking it one Proof of Life moment at a time

He didn’t just want to hit the 98-mph heater from Seranthony Dominguez over the fence. Francisco Alvarez wanted to vault it over the clouds, over the sky, maybe all the way to the Whitestone Bridge. He settled for 421 feet. That was enough.

That gave the Mets a 4-3 win over the Orioles, gave them a 1-0 head start on a 10-games-in-10-days obstacle course that will deliver them to Labor Day weekend and either solidify their status as postseason hopefuls or expedite the franchise’s gaze to 2025. Some blasts are bigger than others.

This one was king-sized, both for a team looking to negotiate a minefield of Orioles, Padres and Diamondbacks , and for a kid catcher who’d been wandering in the weeds for almost two months. Until the moment bat collided with baseball, Alvarez had only seen one ball clear a wall since June 26. He’d frittered 64 points off his batting average since then, 206 points off his OPS.

“It’s been hard for him,” Mets manager Carlos Mendoza said. “He’s been struggling, 22 years old at the big-league level. He cares so much and he wants to win so much, at times when we’re struggling he feels like he’s responsible, he has a lot on his plate. His at-bats have been better but we haven’t seen that a lot in games.”

They saw it now, and it was a glorious sight for teammates spilling out of the first-base dugout, eager to swarm Alvarez, too impatient to wait for him to reach home plate. So half of them got to him halfway to first. Alvarez didn’t mind. He wasn’t in a hurry. He’d never hit a walk-off home run before. He was going to savor it.

“I was very excited,” Alvarez said. “They are a very good team and we were able to beat them.”

If you wonder why sometimes opponents have annoyed expressions on their faces … well, the Mets do enjoy their celebrations. There’s the “OMG” stuff over and over. There was Luis Severino and Alvarez on Saturday, celebrating like Larsen and Yogi in ’56. There was Alvarez on Monday night, barely breaking the four-minute home-run trot.

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That probably wears on a few nerves, sure.

But they are also legit Proof of Life moments, too. When you think of last summer at Citi Field — and the first two months of this season, too — and remember what a joyless slog it was like here, it’s mostly a change for the better. As Alvarez said: “We’re at home. We have to enjoy these moments.”

Or, think of it this way:

On the morning of Memorial Day, the Mets arose D.O.A.: 22-30.

On the morning of the Fourth of July, they woke up back at sea level: 42-42.

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On Labor Day …

Well, these 10 games will tell us a lot about what kind of good night’s sleep the Mets and their fans will enjoy a week from Monday , after two more with Baltimore, four in San Diego and three in Phoenix. And it’s funny. It’s really not supposed to be this way in baseball. Football? Sure. The thing I miss most about the “Mike and the Mad Dog” show were these annual chats in which the lads engaged:

DOG: Week 1 … Giants home to the Cardinals …

MIKE: That’s a win.

DOG: One-and-oh! Week two. Giants, home to the Lions …

MIKE: That’s a win.

DOG: Two-and-oh! Week three, Giants at the 49ers!

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MIKE: Dog, that’s a loss …

Football? Sure. Baseball? Nobody with full retention of their sanity would ever dare go game-by-game across all 162, and nobody other than Francis of Assisi would even think to smile and listen to all of that without running for the door. And, frankly, St. Francis himself would probably beg you to stop by the time you reached April 15 or so.

Still. In small samples, it’s hard to resist.

In this small sample size, the Mets are 1-0. Mendoza saw his kid catcher — one homer in 54 days — work the count to 3-and-0 and decided: Let’s give him the green light.

“I appreciated that,” Alvarez said. And soon, the ball was careening toward Cambria Heights. One game down in a 10-game gantlet, nine to go, 1-0 so far.

“Who we’re playing doesn’t matter,” Mendoza, said. “It’s our job to get wins and we’ll treat it that way no matter what. We’re not looking that far ahead.”

By the time they start, Alvarez might finally reach home plate.

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