#Mike Piazza’s most emotional home run brought entire city to its feet

The night was always going to be a memorable one when the Mets hosted the Braves at Shea Stadium on Sept. 21, 2001, in the first sporting event in New York City following the 9/11 terrorist attacks that brought down the Twin Towers.

Mike Piazza’s home run in the eighth inning made it historic.

With Mets players and coaches wearing hats representing the NYPD and FDNY, an emotional pregame tribute to the victims of the attacks and multiple standing ovations for mayor — and Yankees fan — Rudy Giuliani was followed by a tight game.

The Mets trailed Atlanta 2-1 in the bottom of the eighth when Edgardo Alfonzo drew a one-out walk off Steve Karsay and was replaced by pinch-runner Desi Relaford.

Karsay, upset about the 3-2 pitch that resulted in the walk, then had to face Piazza, who had already doubled twice in the game.

Piazza crushed an 0-1 pitch just to the right of the camera towers beyond the center-field fence and sent the crowd of 41,235 into a frenzy.

“I’m just so happy I gave the people something to cheer,” Piazza said after the game. “There was a lot of emotion. It was just a surreal sort of energy out there. I’m just so proud to be a part of it.”

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Armando Benitez picked up the save with a scoreless ninth to give the Mets their fourth straight win and 10th in their previous 11 games. And it brought the Mets, who were 13 ½ games out on Aug. 17, to within 4 1/2 games of first-place Atlanta in the NL East.

“If the season ends tomorrow, we’re all winners, because we didn’t give up,” Piazza said. “I was glad to come through and give these people something to cheer for at last. That’s why they came out, to be diverted from the sorrow and the loss.”

They eventually pulled to three games behind the Braves, but never caught Atlanta and missed the playoffs.

But their late-season push in the weeks following the attacks resonated with the city — and still does.

In 2004, Piazza told The Post’s Mike Vaccaro he wanted “to cry the whole night. But you’re a pro. You have a job to do. And as an athlete you’re used to blocking things out, focusing on the moment at hand.”