Why ‘Boston’ Rob Mariano wasn’t a fan of bestie Dylan Efron’s first ‘DWTS’ performance

Rob “Boston Rob” Mariano admittedly wasn’t impressed by his “Traitors” co-star-turned-bestie Dylan Efron’s first “Dancing With the Stars” performance.

Efron’s debut performance on the current season of “DWTS” was a cha cha to Kelis’ iconic 2003 hit “Milkshake” with pro partner Daniela Karagach.

“After the first one, I was like, ‘We got to talk about the song choices,’” the “Survivor” legend tells Page Six’s “Virtual Reali-Tea” with a laugh while promoting his new Dunkin’ and Kahlúa collab, “It’s Kahlunkin’.” “Because that ‘Milkshake’ … [I] was not coming to the yard.”

Still, Mariano says he’s been in Efron’s corner — in his own tough-love kind of way. “I cut him down,” he jokes. “I said, ‘Listen, bro. The show’s not over ’til it’s over. Even after the dance, you look at the judges, make sure you smile. I want to see some fist pumps like this show’s still going.’”

The Boston native may not be eager to show off his own moves, though. When asked if he’d ever consider competing on “DWTS” himself, Mariano doesn’t hesitate to shut it down.

“I don’t,” he says flatly. “That’s the thing. Like, I’m not going on the dance floor.”

Instead, Mariano is happy cheering Efron on from the sidelines — a role that perfectly fits the unlikely bromance that began when the two met filming Peacock’s hit series “The Traitors.”

“We just vibed based on, like, we both have a shared sense of adventure and competition,” Mariano explains. “And he’s just a good guy, you know, and I like that.”

The reality star says their connection transcended the show’s infamous backstabbing and deceit. “Inside the house or the castle or whatever it is, when you’re cutthroat and murdering people and trying to kill ’em, you’re playing a game,” he says. “But as soon as that’s over, we just connected on a regular level.”

Now, that friendship is turning into something bigger. Mariano teases that he and Efron recently teamed up for a new project that fans will get to see soon.

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“Dylan and I actually worked on a different project that’s going to be coming out soon,” he reveals. “It’s kind of like a little bit docuseries, YouTube format, a little being competitive.”

As for what’s next in Mariano’s own reality career, he admits the days of playing the cutthroat strategist might be behind him.

“As a competitor on these shows, I feel like it’s been 25 years,” he says. “I kind of have a reputation now where they might let me stay a little while but they’re going to be coming for me. So I feel like my days as a competition reality person might be over.”

Still, he’s not done entertaining fans just yet. “I’d like to move into other aspects [of entertainment],” he says — preferably ones that don’t require a cha cha to “Milkshake.”