Five people ended up in hospital and two were arrested after Ontario’s Brandon Cook stunned home favourite Steven Butler to land the North American IBF and WBA light middleweight titles in Montreal
Butler walked across the ring and even appeared to be pushing his conqueror towards the bucket as it flew across, smashed into Cook's face and floored him.
A groggy Cook finally fled the arena with his team before he was taken to hospital and later released.
Security guards eventually quelled the mass fighting around the Bell Centre.
A 22-year-old man was charged with assault and another man, 23, faces an accusation of armed assault, the Montreal Gazette reported.
Cook told Canada's Global News: "I'm pressing charges because no athlete should ever have to deal with that."
He added: "All of a sudden he (Butler) pushed me into the way of a flying object I thought was a bottle.
"But it was a big can. It was pretty heavy, it was one of the hardest hits of the fight.
"I still can't believe the way that happened. Then fights started breaking out everywhere."
Camile Estephan, president of promotion company Eye of the Tiger Management, condemned the "troubling" and "inexcusable” events.
I agree with him, watch the footage below.