NEW YORK — The man known as Mr. Smile didn’t.

As Francisco Lindor floated to first base within seconds of launching an NLDS-winning grand slam and a bedlam of blue and orange exploded around him, the hero of the hour remained abnormally calm.

His face was flat and stoic, like a calm sea. He didn’t grin, pump a fist, throw a bat or roar to the heavens and beyond. He didn’t turn to his dugout in jubilation. He showed no emotion whatsoever.

“Stone cold,” Mets outfielder Jesse Winker told Yahoo Sports after New York’s 4-1 victory over the Philadelphia Phillies in Game 4. “That guy? He’s a murderer. It’s incredible. He has no heartbeat.”

If Lindor’s ticker throbbed as Citi Field roared him around the bases on Wednesday, he didn’t show it. The Mets’ superstar shortstop jogged his way along the baseline, his eyes glued to the baseball crest out of sight, casually dropped his bat and coolly began his trot as if the stadium were completely empty.

That was most certainly not the case.

Around Lindor, pandemonium. Adults entranced, their bodies overwhelmed by the moment, jumping uncontrollably like primary school children. The faces of fans, coaches and players radiated joyful disbelief. In the stands, an ocean of arms floats happily up into the New York night. Noise enveloped the scene, a symphony of roaring fanatics.

“Great ball players do great things,” Steve Cohen, the club’s billion-dollar owner, beamed after the match in the festive locker room, his eyes obscured by enormous ski goggles. “So calm. He just sat there and saw a speed of 100 miles per hour. Away. Spectacular.”

As Lindor walked across the board, his expression still blank, he was greeted by the trio of Mets he had just walked into. None of Francisco Álvarez, Tyrone Taylor or Starling Marte could stop shining. Marte was the first to receive Lindor. He threw his loin arms around Lindor and lifted the homecoming hero to heaven.

Only then did a smile appear on Lindor’s face.

“He’s the damn man, man,” a grinning Marte, silver grills glinting in his mouth, told Yahoo Sports after the game.

Lindor’s blast was a fitting end to an absorbing, stressful series between these two division rivals. The Phillies entered Game 4 needing a win to extend their season. The Mets certainly didn’t want to head back south for a winner-takes-all Game 5.

Both clubs started crafty lefties on the mound. Neither offense continued until the Phillies scraped together a run in the fourth on an infield dribbler off the bat of Alec Bohm, who rumbled Mets third baseman Mark Vientos to the turf. Bryce Harper rushed home to record the first point of the game.

It remained 1-0 until the sixth, until Lindor changed the story.

The Phillies sent reliever Jeff Hoffman, who had entered in the fifth after warming up several times early, back out to start the sixth. That would prove costly. The first three Mets reached base on a single, hit by pitch and walk. Hoffman hit two wild pitches; his control had failed him. After the first out of the inning, a force at home keeping the bases loaded, Phillies manager Rob Thomson came out to get rid of Hoffman.

Carlos Estévez came in to face Lindor. Estévez, a pleasant, easy-going Venezuelan the size of a refrigerator, was Philadelphia’s most important acquisition at the trade deadline. For most of the second half, he thrived as a reliable late-inning option in Philly’s bullpen. His only bugaboo: a tendency to give up the occasional home run.

Estévez started Lindor with three consecutive fastballs. Two missed the zone, one zoomed past the shortstop’s bat for a hit. With the score 2-1, the reliever returned to his triple-digit heater, in much the same spot as the pitch Lindor smelled.

But this pitch took a little too much off the plate. Lindor did not miss this throw.

It was the kind of swing that franchises fantasize about. There is a mural in Philadelphia’s Citizens Bank Park of Bryce Harper’s iconic homer in the 2022 NLCS. It will remain there until the stadium collapses.

Lindor’s grand slam will rightly receive the same treatment. They will play it again and again on SNY. Photos of it will line the concourses of Citi Field. People will have shirts made. For decades, Mets fans will climb up on bar stools, order a few and ask each other, “Do you remember when?”

The rest of the game wasn’t just an epilogue, though. Philadelphia should have had a two-out rally in the eighth, but an Alec Bohm ball over the bag was incorrectly ruled a foul. Then, in the ninth, closer Edwin Díaz walked the first two batters he faced, bringing the tying run to the plate. A strikeout by Kody Clemens and a flyout by Brandon Marsh cooled the nerves.

Díaz ended proceedings with a fastball from Kyle Schwarber. The Mets ran out of the dugout – not towards the pitcher as teams usually do, but towards the shortstop. Lindor disappeared among a crowd of blue.

“I’m enjoying the moment. I live in the moment,” he said at his post-game media conference. “A lot of people ask me why I don’t respond, why I don’t respond to the home runs. I respond, you know. I celebrate inside. But in the end the job is not done until we have played 27 zeros.”

After the required zeros were recorded, Lindor was a ball of joy and wandered around the field with his daughter in his arms. He took about 100 selfies with several friends and family members gathered on the Citi Field grass.

He certainly smiled at every last one.