The Mets' J.D. Davis celebrates his 10th-inning walk-off single against...

The Mets' J.D. Davis celebrates his 10th-inning walk-off single against the Indians with his teammates at Citi Field on Wednesday. Credit: Jim McIsaac

Brodie Van Wagenen wasn’t stripped to a tank top, like Wednesday’s hero J.D. Davis, whose uniform jersey was yanked from his torso by Pete Alonso after the walk-off single that delivered the 4-3 victory over the Indians in 10 innings.

No, the unlikely architect of these Mets, the man responsible for transforming Citi Field into the Happiest Place on Earth, was still wearing his summer-weight suit, the shirt still buttoned, when he appeared in the clubhouse afterward.

Van Wagenen’s uniform was the same as everyone else’s — an ear-to-ear grin, as much a part of the Mets’ garb these days as the colors blue and orange. The GM congratulated Todd Frazier, then Amed Rosario, then Pete Alonso, then Davis, who already is going down in Flushing lore as one of the greatest trades in franchise history.

Davis flat-out exhausted Indians closer Brad Hand in the 10th. You could see it. Pitch after pitch, slider after slider. The sign says Citi Field, but 41 Seaver Way is Davis’ House. Hand just didn’t know it yet, not until the ninth pitch, which Davis smacked into leftfield for his first career walk-off winner.

Six of the last seven times Davis has driven in a run, he’s either tied the game or given the Mets a lead. He already was batting .390 with 10 homers and a 1.186 OPS in 48 games at Citi before Wednesday’s dagger. Davis has been as responsible for the Mets’ revival this season as anyone in that clubhouse, and more than most. So I joked with Brodie about where I’d list the offseason trade with the Astros that netted him Davis.

Maybe No. 1 all-time? Right above Yoenis Cespedes and Mike Piazza?

Van Wagenen’s smile grew bigger. It didn’t seem possible, but it did.

“We’ve still got a long way to go,” the GM said. “But it’s good to see.”

There were 28,349 people inside Citi — minus a few Indians fans — that couldn’t agree more with Van Wagenen. To them, to the Mets, these games feel like October. With every ounce of the excitement, and plenty at stake. This isn’t the elimination round yet, but as Davis said after Tuesday night’s victory over the Indians, these are the playoffs. Don’t let the calendar fool you. 

“I’ve been saying it for a while, this is a special team,” Davis said. “It was just a matter of time before we hit on all cylinders.”

Even when they did start winning, all the Mets heard was how they did it against weak competition, that the streak was a mirage, that a reckoning would come.

But here’s what happened instead. The Mets managed to beat whoever showed up, and with these two victories over the Indians — another series W over a playoff contender — they’re now 12-1 over their last 13 games at Citi Field. Mickey Callaway & Co. also won in their final at-bat Wednesday for the 17th time this season, which was their fifth walk-off victory.

As improbable as this season-saving streak has been, Wednesday was right up there in degree of difficulty. The Mets lost Marcus Stroman after only four innings due to left hamstring tightness, then later fumbled a 2-1 lead when Brad Brach allowed a Jose Ramirez triple in the sixth. Luis Avilan got to within a strike of holding the line in the 10th before Carlos Santana took him over the leftfield wall for a two-out homer.

In most cases, that was a demoralizing gut punch, if not the finisher. But for these Mets, they just needed a minute to catch their breath. As soon as Amed Rosario led off the 10th with a bullet double, the Citi Magic was stirring again.

“You can definitely sense it,” Callaway said. “People running up and down the dugout, saying, ‘We can do this!’ These guys believe in themselves.”

Somewhere, Tug McGraw is smiling. But these Mets don’t just believe anymore. It’s almost like they expect to do this on a nightly basis. The Indians helped out when they failed to turn what would have been a game-ending double play in the 10th, and Wilson Ramos kept the rally alive with a swinging bunt before Davis’ dramatic blow.

As Davis spun around second base, Alonso and Rosario raced to him, with the Polar Bear tearing off his jersey, just as he did to Michael Conforto after the walkoff homer to beat the Nats. Like the Mets themselves, there’s really no explaining it.

“You hit a walk-off, your shirt’s coming off,” Alonso said.

Makes as much sense as everything else these days at Citi. And for the Mets, it’s all fun.

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