Adrien Broner went off the rails Saturday night in a post-fight interview after pretty much getting destroyed by Manny Pacquiao for the WBA welterweight championship ... telling Showtime's Jim Gray he could beat the crap out of him if he wanted.
Pacquiao dominated the fight -- pretty much everyone but Adrien agrees -- and Broner went on a tirade with Gray, who warned him to keep it civil or else he'd pull the plug on the interview.
Broner suggested the fight the MGM Grand in Vegas was rigged, but Gray stood his ground .