Doc Rivers knows he crossed a line when he LOST HIS MIND on an NBA ref Tuesday night -- saying plain and simple ... he shouldn't have acted that way.
The outburst went viral -- Clippers players had to restrain Doc from going after ref Ken Mauer when he was issued a technical foul for talking to another ref during the 1st overtime period against the Nets.
"Yeah, you don't act like that," Doc told us at Catch in West Hollywood this weekend ... "You should get thrown out for that."
Don't worry ... Doc says he's cool with Mauer too -- calling him a good guy.
There's more ... we also asked Rivers about certain NBA players saying they would boycott a White House championship visit during Trump's administration. It's clear he's NOT on board with that.