Buck Showalter has managed 678 regular-season games for a New York club, but Tuesday’s game will be unlike any that came before.

During his tenure leading the Yankees from 1992-95 and throughout the initial 96 games of this season, Showalter never has taken part in the Subway Series, which did not exist until interleague play began in 1997.

Instead, some of the most pressurized matchups he encountered with the Yankees were exhibitions that did not matter to everyone, but mattered deeply to George Steinbrenner. Showalter recalled the Mayor’s Cup — an exhibition between the Yankees and Mets to close spring training in the early 1990s, an offshoot of the Mayor’s Trophy games from years prior.

“There were certain must-win games over there,” Showalter said Sunday. “When we went to St. Lucie [against the Mets]. When we went to Winter Haven to play the Red Sox.”

Twenty-seven years after Showalter last managed a Yankees game, the stakes are different in his first time squaring off against the Yankees as Mets manager. The two games might mean more than the other 160 to a fan base that wants bragging rights, but they matter to the Mets simply because every game matters during a dogfight atop the NL East.

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Buck Showalter will finally manage a Subway Series game on Tuesday night.
Corey Sipkin

“We’re getting ready to face a real good baseball team,” Showalter said ahead of the two-game Citi Field showdown that begins Tuesday.

The Mets enter having lost three of four and with bats that have cooled off as the weather has gotten hotter. Their offense has scored just 4.05 runs per game this month, prompting a trade for Daniel Vogelbach with at least one more offensive upgrade expected before the Aug. 2 trade deadline.

The Mets have succeeded all season by stringing hits together, which has too often failed recently, and their lack of power has been highlighted. In their past six games, they have two home runs — or half as many as Aaron Judge has slugged in his past six games.

The Mets’ best answer to Judge provided their offensive jolt in Sunday’s win over the Padres, in which Pete Alonso drilled his 25th home run.

“I wouldn’t really call it toe to toe, me versus him,” Alonso (82 RBIs) said of Judge (81), who finished the weekend as MLB’s two top run producers. “This is the New York Mets versus the New York Yankees. This is going to be a great moment for New York. This is a moment where the city can come together over the game of baseball — obviously you have a side you pick — but this is going to be a really fun time for the city of New York, and I’m really excited.”

The Mets should be happy with the pitching matchups, as Taijuan Walker — perhaps their first-half MVP — will face Jordan Montgomery before Max Scherzer is expected to pitch Wednesday against Domingo German.

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Pete Alonso
Corey Sipkin

As their offense has dipped, their rotation has dominated. Mets starters have reeled off 14 straight games in which they have surrendered two or fewer runs, the longest streak since Brewers starters ran off 15 such games in a row in 2019.

The Mets rotation’s ERA through that span is 1.58. But no team has scored more than the powerful Yankees, who are averaging 5.36 runs per game this season, so Walker and Scherzer will be tested.

“You’ve got two excellent teams that are in first place playing against each other,” Alonso said. “It’s going to be a great environment, it’s going to be two highly, well-contested games.”

Games between two teams that are a combined 57 games above .500 — while the Braves, just off the Mets’ pace, are amid a series in Philadelphia against the middling Phillies.

The two-game set will mean something to New York, and Citi Field is expecting substantial crowds, but the Mets’ focus remains on themselves and their division.

Asked what he knows about a Subway Series that he finally will experience 30 years after managing his first game in The Bronx, Showalter did not look across to the other dugout.

“I know who’s pitching for us Tuesday,” he said.

— Additional reporting by Mike Puma A