The LeBron James free-agency rumor mill is officially in overdrive.

With the Cleveland Cavaliers one loss away from being swept out of the NBA Finals, speculation is already running rampant about where he will head this summer. Seemingly everyone has come to grips with it not being Cleveland.

As for some dark horses, ESPN.com's Chris Haynes has a few answers.

"I'm going to throw out a dark horse: the Toronto Raptors. I'm gonna throw out the Toronto Raptors, and let's not overlook the Boston Celtics," Haynes told The Athletic's Tim Kawakami (via Tom Westerholm of MassLive.com). "I think the Boston Celtics are in that realm with Golden State. If Boston reached out and said 'We're serious,' LeBron would listen."

Both Boston and Toronto are exceedingly unlikely destinations for LeBron. First of all, both are already over the salary cap for 2018-19. Neither the Celtics nor the Raptors could add James without making multiple moves to clear space.

The Celtics also have Kyrie Irving, who requested a trade last summer from Cleveland in part because he no longer wanted to play with James. Boston would likely have to move Irving if it wanted LeBron—even though the pair seemed fine during their brief reunion at the 2018 All-Star Game.

Toronto has no history of landing major free agents of LeBron's magnitude. James' Cavaliers also swept the Raptors out of the playoffs each of the last two seasons. LeBronto jokes aside, the fit isn't great here.

The main contenders for James remain the Philadelphia 76ers, Houston Rockets and Los Angeles Lakers. The Sixers and Rockets present the best basketball opportunities, while Los Angeles gives LeBron a chance to be closer to his off-court ventures during the season.