Post reporter wears Mets Grimace costume with Yankees fans in the Bronx

The Mets and the Yankees may be crosstown rivals — but I was able to transcend the bad blood by dressing up as none other than Grimace in enemy territory.

Well, for the most part, that is.

As both of the Big Apple’s beloved MLB franchises were in action Thursday night, I decided to test the waters and head to the Boogie Down in the Mets’ unofficial good-luck mascot Grimace costume.

But there were a few notable caveats.

I draped some Yankees bling around my neck, and rooted for the Bronx Bombers as the lovable McDonald’s character that’s been a charming rallying cry for the Mets this season.

One may think doing so is akin to signing my own death warrant given the history between the two fanbases.

Though when I made it to the shadows of Yankee Stadium, the reception I received was surprising to say the least.

Of course, I was on the receiving end of some Bronx cheers — after all, it is New York.

“Leave that sh-t in Queens,” one Yankee fan watching the game on his phone outside shouted minutes into my venture.

“What are you doing in the Bronx if you’re wearing that,” another man snarled.

Another member of the Yankees faithful just shook his head as he walked by with buddies.

But others got a kick out of spotting the Mets-affiliated fast food icon on a day other than Halloween.

Some were eager to snap photos with the purple monster while the Yankees played Game 3 of the ALCS in Cleveland against the Guardians — and I even got invited, albeit by a Mets fan, into one of the neighborhood’s prime watering holes.

“I thought Grimace was a Mets fan,” a woman told me as she took a picture.

And another woman wearing a Mets shirt later told me I was a “champion” for gearing up as Grimace in the Bronx. She later passed by me again and told me she was shocked that the get-up was still inflated.

The bar I was welcomed into was filled mostly with Yankees fans, and as I raised the Yankees necklace, they gave me a round of applause and some laughs.

Ya gotta believe (see what I did there) Mr. Met would have been outright booed, but Grimace is a lovable fixture that can rise above the rivalry.

Before I could ask about a Yankees-Grimace collab with patrons, I was asked to leave because the bar was hosting a private party. To be fair, my giant purple behind was also blocking some fans from watching the TVs.

One Yankees fan outside the bar told The Post his team doesn’t need gimmicks.

“Teams used gimmicks for certain reasons, but the Yankees are so old school tradition,” he said, citing the team’s strict no beards rule for players. “They stand on that for so many years, they haven’t changed and I stand with it, I get it.”

But one young woman who works at the Bronx ballpark was bold enough to declare, “Grimace is always at Citi Field, but he should be a Yankees stadium.”

Throughout the night, regardless of team loyalties, the photo requests and waves were common. No one tried to push me over. That would only happen in Boston or Philadelphia.

I’m sure after this baseball season ends, the legend of Grimace will endure. Let’s be real, there’s no way the Hamburglar would get this reception.