The war of words between Amir Khan and Paulie Malignaggi descended into a brawl as the boxers weighed in ahead of their WBA light-welterweight title fight.
Champion Khan and New York challenger Malignaggi weighed in amid noisy scenes as a group of the Englishman's fans chanted their hero's name and booed the American.
And when the two fighters went head to head for pictures, they touched heads and were seen arguing before they began pushing each other.
No punches were thrown by the protagonists but chaos erupted as others became involved and the stage filled with people.
Malignaggi's promoter Lou DiBella said: "The public was not supposed to be here. One more thing like this and I'm pulling (Malignaggi) out of the fight. My guy got roughed up by his people. Some gentleman. Go back to England."
Malignaggi weighted in at 139lb, with Khan just half an ounce heavier.
Khan is set to defend his title in the early hours of Sunday morning having already said he wanted to make Malignaggi pay for his accusations of doping in trainer Freddie Roach's camp.
Khan, 23, said he felt the trash-talking Malignaggi had crossed a line when he questioned Wild Card Gym stable-mate Manny Pacquiao's reluctance to agree to blood testing ahead of any potential fight with Floyd Mayweather.