Mets' Pete Alonso reacts after he hits his 53rd home...

Mets' Pete Alonso reacts after he hits his 53rd home run to break the single-season rookie record against the Atlanta Braves at Citi Field on Sept. 28, 2019. Credit: Kathleen Malone-Van Dyke

Completely stone-faced as most of those around him began screaming, Pete Alonso took several steps toward first base, subtly dropped his bat and watched with everyone else as his high fly ball cut through the humid Queens air.

Only when the ball landed in the first row of seats in right-centerfield, ensuring Alonso’s newest place in baseball history, did that change. His stoicism became jubilation, his silence gave way to a yell and his nonchalant pace quickened to a jog as he raised both arms in celebration.

Alonso made history — again — Saturday night in the Mets’ 3-0 win over the Braves. His 53rd home run broke the major-league record for a rookie season, one more than the Yankees’ Aaron Judge, who had 52 in 2017.

“After I hit it, I just wanted to see it and enjoy the moment a little bit,” he said. “It’s just a magical moment. It was incredible. It’s magical. That’s the only way to describe it. I couldn’t have asked for a better rookie year. This is a fantasy come true.”

The record-setting shot came in the third inning against Atlanta’s Mike Foltynewicz, who threw a 93-mph meatball two-seamer over the middle of the plate. Alonso crushed it, and the Citi Field PA system blared the theme from “The Natural.”

By the time Alonso crossed the plate, half of his team had emptied out of the dugout for hugs and handshakes. Upon reaching the top step, he raised both arms again and pointed to the crowd, soaking it all in before making his way into the dugout.

By the time Alonso took the field for the top of the fourth, as the grounds crew replaced the bases, he had tears in his eyes. When the inning began, he swallowed the lump in his throat, took a big breath and pounded his glove with his bare hand, readying for each pitch by Steven Matz (six scoreless innings). “I didn’t know I was going to be overcome with all that emotion,” he said. “At that point, might as well let it out. It was crazy.”

And what was running through Alonso’s mind when the tears came? “Holy . . . ,” he said. “I can’t believe that happened.”

Said Mickey Callaway: “This kid has done amazing things this year. The fans came here to see something historic, and they got what they wanted to see. It’s like he never lets you down.”

Alonso got the ball — the most meaningful of his many keepsakes this year, he said — back from the family that caught it. To thank them, he took them onto the field, signed a few autographs and posed for pictures.

About a half-hour later, with the Mets’ clubhouse long since emptied out, Alonso returned to the field with his parents, Pete and Michelle, his fiancee Haley and other relatives and family friends. More photos, more hugs, more memories.

The ball still was in his back pocket. “To have this type of stuff, it’s really special,” he said. “To have little mementos and little trophies, I guess you could call them, to me, it’s results of hard work.”

Heading into the final day of the season Sunday, Alonso leads everybody in home runs and holds a comfortable lead over the Reds’ Eugenio Suarez, who has 49. Alonso is on the brink of becoming the first rookie in the modern era (since 1900) to finish a season as the majors’ outright homer king and the first Mets player ever to do so. 

If he plays, he will face Braves righthander Mike Soroka, perhaps the second-best rookie in the National League this year.

That will mark the end of a season in which Alonso earned the first base job in spring training, became an All-Star, won the Home Run Derby, coined the team’s new slogan (“LFGM”), set the franchise single-season homer record, organized a 9/11 tribute by buying teammates specially made cleats honoring first responders, and passed Judge.

Alonso is 199 homers away from tying Darryl Strawberry (252) as the Mets’ all-time leader. He can get there with an average of 42 per season for the six seasons he is under team control before his scheduled free agency.

Quizzed on the subject Saturday night, Alonso — a history major in college with a knack for fun facts, he often notes — knew Strawberry held that mark but didn’t know the total. And he didn’t want to know just yet.

For now, 53 as a rookie is enough. “I’ve never felt anything like that,” he said. “It was just euphoria.”

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