NEW YORK -- Upon jogging around the bases for the 42nd time this season, then wading his way through a dugout gauntlet of high fives, arm bumps and bro-hugs, Pete Alonso emerged back onto the field for a curtain call. Rather than tip his cap, as is the usual custom, Alonso stared up at Citi Field’s seating bowl, clasped both hands together and pointed to the crowd. He called it his “love signal” to a fan base enamored with him.

In a season that could still end any number of ways for the Mets, Alonso has been the team’s most consistent offensive force. He now has a signature record to prove it, hitting his 42nd home run Tuesday to take sole possession of the Mets’ single-season mark. Snapping a tie with Todd Hundley and Carlos Beltrán, Alonso became the first rookie to set his franchise’s homer mark in more than three-quarters of a century.

• Alonso part of a rare rookie HR club

“It’s mind-boggling,” Alonso said. “There are so many great players that have come through this organization, that have played here for a long time, that are Hall of Famers, that are champions, that are just absolutely well-respected throughout the game. It’s very humbling, because those people, in my eyes, are legends of the game and also legends here in New York.”

That the record-breaker came in a 5-2 loss to the Cubs -- dropping the Mets three games behind Chicago for the second National League Wild Card spot -- was the only disappointment for Alonso, who leads the Majors with 20 game-tying or go-ahead homers. His 42nd long ball was an opposite-field shot of the latter variety, giving the Mets a one-run lead in the fourth inning against Cubs starter Yu Darvish. It wound up being the Mets’ only lead of the night. Not long after, Addison Russell and Javier Baez hit two-run homers off Marcus Stroman, turning Game 1 of a pivotal three-game series in Chicago’s favor.

• Box score

Still, that did nothing to tarnish the individual achievement of Alonso, the odds-on favorite to win the NL Rookie of the Year Award. One of the Mets’ top prospects heading into Spring Training, Alonso broke camp with the team, hit his first home run four games into the season and has not slowed his pace since. In July, Alonso made his first All-Star team and won the Home Run Derby. In August, he set the NL rookie home run record.

Now, he owns the Mets’ all-time mark.

“It’s a pleasure to have a fine young player like Pete Alonso break my record,” Beltran, now an advisor for the Yankees, said in a statement. “I have not met Pete personally, but people have told me he plays the game with passion and doesn’t give up on any at-bat. He has had great success in his first year.”

As far as franchise records go, the Mets’ is among Major League Baseball’s most modest -- but it may not stay that way for much longer. Alonso still has 4 1/2 weeks to add to his total; at his current pace, he would finish with 52, matching Aaron Judge’s all-time rookie mark set in 2017 with the Yankees. Alonso is also on pace for 125 RBIs, which would break the club record of 124 that Mike Piazza and David Wright share.

Alonso is already the first rookie to stand alone as his franchise’s single-season home run king since Johnny Rizzo for the Pirates in 1938.

“To me, he’s more than a power hitter, he’s a pure hitter,” Hundley said. “I have seen five or six of his games and he keeps getting better and better. He has just had a tremendous year.”

For Alonso, only two questions remain: how high he will extend his new record, and how capable the Mets will be of parlaying that success into a postseason berth. Tuesday marked the start of a critical 12-game stretch for the Mets, who will spend the next two weeks exclusively playing teams ahead of them in the NL Wild Card standings. By the end of it, the Mets will have a far better idea of their postseason fate.

Their first act was a losing effort that left Stroman insisting he has to pitch better and Alonso imploring others to share his optimism.

Alonso may have a record, but he wants a good deal more.

“There have been so many people who wrote us off, and are still continuing to write us off,” Alonso said. “We’re just going to keep on working to do the best we possibly can and make the playoffs. From where we were to get where we are now, that’s a huge accomplishment in itself. And the job’s not done yet.”