The trade talks between the Boston Celtics and Los Angeles Clippers are still at an impass, but it is remains unlikely that Doc Rivers will return as head coach of the Celtics for the 2013-2014 season.

And if this report from Chris Sheridan is true, then, well, we now know why Rivers does not want to return.

According to Sheridan, Rivers once tried to fight Celtics' guard Rajon Rondo in the locker room when Rondo cursed at the head coach during a team meeting.

A source close to the Celtics tells Chris Sheridan of SheridanHoops.com that Rondo droopped an F-bomb on Rivers in the locker room during a team meeting, and Rivers went after Rondo and tried to fight him before the fracas was broken up.