ATLANTA -- With 42 games left to play, Pete Alonso’s season already ranks among the more productive campaigns in Mets history. Alonso has owned the franchise’s rookie home run record for weeks; Thursday, in a 10-8 win over the Braves, he hit his 39th to match Cody Bellinger for the most by a rookie in National League history.

Passing Bellinger seems a foregone conclusion, as does the Mets’ overall franchise record for homers: 41, which Todd Hundley and Carlos Beltran share.

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Beyond that, two significant standards loom: the Major League rookie home run record, which Aaron Judge set with 52 in 2017, and the Mets’ overall RBI record, which Mike Piazza and David Wright share with 124. Alonso is just ahead of the pace needed to set the former, and a hair behind the rate required for the latter.

At this point, doubting his chances to reach either mark would be folly.

“There are a lot of records out there,” Mets manager Mickey Callaway said. “I know he’s not too worried about that. He just wants to put together good at-bats and play good defense. But he’s stockpiling them.”

Many of Alonso’s home runs have resembled the one he hit Thursday: a 110.6-mph, 451-foot shot to straightaway center field, according to Statcast data, one of nine he has hit at least 440 feet this season. (No Major Leaguer has more.) Alonso also singled home two runs in the fifth inning and another in the seventh, finishing with a career-high five hits and six RBIs. He and shortstop Amed Rosario became the first pair of Mets to collect five hits in the same game in franchise history, while Rosario became just the sixth to have four-plus hits in multiple games.

“I’m really happy,” Rosario said through an interpreter, “but I’m also really happy for him because he was able to tie the rookie record for home runs.”

On Thursday, conditions were ripe for padding statistics. The Mets rapped out 23 hits for just the fifth time, relying on five apiece from Alonso and Rosario; four from Wilson Ramos; three from Juan Lagares; and at least one from five other players. It was enough offense to knock Braves starter Julio Teheran out in the second inning, and enough to hold on for victory even after Drew Gagnon allowed four home runs in the eighth and ninth innings, forcing Edwin Díaz to record the final out.

For the Mets and Braves alike, it was a night to pump up batting averages and round out the backs of baseball cards. For Alonso in particular, it was a day for affirmation.

Earlier this week, Callaway sat down with Alonso to urge him not to worry about his relative lack of production since the All-Star break. Although the rookie entered Thursday’s play with a .181 average in the second half, that included eight home runs and 17 RBIs in 30 games. Over the past three weeks, Alonso has gone deep even more frequently than he did before the break.

“I want to be the best version of myself every single day,” Alonso said. “Baseball’s a game of failure, and that’s really difficult to do and maintain throughout 162 games. I felt like the second half, it really hasn’t been what I’ve wanted after having the first half I had. … I was kind of just frustrated after a while because I know that I’m better.”

Games like Thursday provide the proof. Record books already hold the evidence. Time will tell how many all-time marks Alonso will ultimately set, though he’s about to have one more all to himself.

“I don’t stand alone,” Alonso said of the NL rookie record. “I’m tied. Hopefully, I keep on going and keep pushing forward. Hopefully, I can stand alone in that category.”