Michael Sam EXPLODED on a guy outside of a West Hollywood club Tuesday night -- saying he gives "our community a bad f***ing name" ... and warning him he was about to catch an ass whoopin'.
It all went down outside of Bootsy Bellows, where the ex-football player (who's still in massive, athletic shape) had been hanging out with a group of friends, including EJ Johnson.
But when they got to the cars, Sam and a man in a white shirt began to yell at each other.
"People like f***ing you give our community a bad f***ing name," Sam roared ... before calling the other man a "trifling ass bitch."
At one point, Sam warns the guy not to put his hands on him -- and says what sounds like, "Touch me, I will find that you tried to attack me and I will lay your ass on the ground."
Eventually, Sam got into a waiting car and left without further incident.