Kyrie Irving’s return to Boston was always going to be hostile and heated. Now it’s almost guaranteed to be elevated to pure hatred after the Nets star essentially called out Celtic fans’ behavior during his stint there, and hoped they’d refrain from any “racism” and “belligerence” for Friday and Sunday’s games at TD Garden.

“It’s not my first time being an opponent in Boston. So, I’m just looking forward to competing with my teammates,” Irving said on a Zoom press conference after Tuesday’s Game 2 win. “And hopefully, we can just keep it strictly basketball, there’s no belligerence or racism going on — subtle racism — people yelling s–t from the crowd.

“But even if it is, it’s part of the nature of the game and we’re just going to focus on what we can control.”

Asked if he’d had racist comments directed at him while playing in Boston, Irving implied he and others had.

“I’m not the only one that can attest to this. But it’s just … it won’t …,” Irving said, with a resigned laugh. He threw his hands up and added, “It is what it is.”

At that point, a voice off-camera chimed in, “The whole world knows it.” To which Irving agreed, “The whole world knows it.”

Some have suggested that voice belonged to Kevin Durant, who was nearby and followed on the next Zoom call.

What’s beyond doubt is that Friday’s Game 3 — which Brooklyn goes into with a 2-0 series lead — will see the Celtics fans at full froth, even with only 25 percent of TD Garden’s 19,580 capacity permitted. It’ll be “near full capacity” for Sunday’s Game 4.

Irving spent two up-and-down years in Boston. His leadership was poor, the 2018-19 results were disappointing and, after initially expressing a desire to stay, did an abrupt about-face. The West Orange (N.J.) product joined the Nets in June 2019.

One has to wonder whether Boston’s well-documented complicated history with race played a role in him leaving the city.

Irving’s close friend Brett Carroll revealed in a to-be-released book “Can’t Knock the Hustle” that the guard had concerns about Beantown’s racial history.

“And then he also realized, ‘Wait a minute. I’m trying to champion Boston, but now that I’m looking at the history of Boston, is this a city that I want to champion?’ ” Carroll wrote. “In terms of their racial history and stuff like that … is Boston the type of place I want to represent?”

Ultimately the answer was no. Or, at least Irving wanted to represent Brooklyn more, which made him anathema in Boston.

Irving missed the Nets’ two trips to TD Garden last season with a shoulder injury. Before the March 3, 2020, game, fans hung pictures of him out on Causeway Street with the label COWARD and his face photoshopped as the Cowardly Lion. After tipoff, many chanted profanities about Irving.

This season, he scored 37 in a Christmas Day laugher in Boston, but it was played without fans due to COVID-19, as was the Nets’ preseason win in TD Garden just days earlier.

This weekend’s return was bound to get nasty. But Irving’s comments stirred the pot and threw in flaming oil for good measure.

Still, this is not a new discussion.

Bill Russell — who tried to get out of having his jersey retired by Boston for the same reason — once dubbed the city “a flea market of racism.” Outfielders Torii Hunter and Adam Jones have both recounted being called the N-word multiple times by Red Sox fans at Fenway, with Hunter putting a no-trade clause in his contract to avoid being sent there.

DeMarcus Cousins said a TD Garden fan used racist language toward him in 2019, with the fan getting banned for two years.

Ex-Celtic Kendrick Perkins said during NBC Sports Boston’s postgame coverage Tuesday “I’ve never heard any player while I was playing … we haven’t heard of any incidents of racism going on, not in my generation.”

Apparently generations before and since have. Even current Celtics guard Marcus Smart opened up in the Players Tribune about racism he’s suffered in Boston, including being called the N-word by a Celtic fan right outside TD Garden.

Celtics coach Brad Stevens addressed Irving’s comments Wednesday on 98.5 The Sports Hub’s “Zolak & Bertrand” show.

“People shouldn’t ever feel like they’re being discriminated against. But I think that everybody is dialed into that now,” said Stevens. “That hasn’t been brought to my attention that that’s happened, maybe but once or twice since I’ve been here, and it was dealt with immediately.

“But maybe it’s happened and guys haven’t talked about it. And certainly, Kyrie had never mentioned anything to me about it, but that doesn’t mean it didn’t happen. And I think that those things should always be taken really seriously.”