Mary Altaffer/Associated Press

It's unclear what team star point guard Kyrie Irving will choose in free agency, but it looks increasingly unlikely to be the Boston Celtics.

According to Ian Begley of SNY, "in recent days, people around Irving have described the probability of him returning to Boston as a free agent as low. Those around Irving also said recently that he hasn't ruled out teams—including the New York Knicks—as possible destinations for him this summer, per SNY sources."

That follows a report from Stephen A. Smith on Tuesday's First Take that Irving was leaning toward committing to the Brooklyn Nets:

And there's always the possibility that Irving will consider a reunion with LeBron James on the Los Angeles Lakers:

Regardless of where he ends up, Irving will help shape the balance of power in the NBA this offseason, along with expected free agents like Kevin Durant, Kawhi Leonard, Klay Thompson, Jimmy Butler, Kemba Walker and Tobias Harris. There's also Anthony Davis, who remains likely to be traded.

The possibilities for where those players end up are endless. The scariest proposition for the other 29 teams in the NBA is that Durant returns to the Warriors. The next doomsday scenario would be Durant and Irving signing with the Knicks and the team pulling off a trade for Davis, putting together a fearsome big three.

It's hard to comprehend that a team like the Knicks, which has been incredibly poorly run for the better part of a decade, could end up Durant, Irving and Davis. But it's certainly a possibility.

There's little doubt that Irving will have plenty of suitors. He remains one of the NBA's most dangerous offensive weapons, averaging 23.8 points, 6.9 assists and five rebounds per game in 2018-19, shooting 48.7 percent from the field and 40.1 percent from three. But he also remains a non-factor on defense and there are questions about his leadership skills after a rocky season in Boston.

The Celtics, meanwhile, could go from the frontrunners to land Davis given their bounty of young players and assets to perhaps not getting involved in negotiations at all if Irving leaves. Would Danny Ainge really trade Jayson Tatum, Jaylen Brown or both players to get Davis without having another superstar to pair him with? And if Irving departs, will Al Horford also consider opting out of his deal and signing elsewhere?

Those are huge questions for the Celtics, and a reminder that Irving's decision in free agency this summer will set off a domino effect all over the NBA.