Eddie Hearn, promoter for IBF middleweight champion Daniel Jacobs, was shocked at the behavior of WBC, WBA middleweight champion Saul "Canelo" Alvarez.

The two boxers nearly brawled during Friday's official weigh-in.

They went face to face after making weight, and they quickly began to butt heads - and then Canelo shoved Jacobs to engulf a full-blown scuffle as both teams had to get involved to pull the boxers apart.

Canelo and Jacobs will collide on Saturday night at the T-Mobile Arena in Las Vegas, with all three world titles at stake.

“I’ve never seen Canelo Alvarez react like that,” Hearn told Sky Sports.

“It was surprising, I think they both instigated it to be honest with you. It surprised me that Canelo even wanted to engage like that.

“You saw that a little bit in the Golovkin 2 fight, but this seemed a little bit more like a fiery Canelo Alvarez. I don’t know if that’s good news or bad news for Danny Jacobs, but he’s definitely rattled. Again, whether that ups his performance or makes him nervous, I don't know. But it’s a nice little edge to a very important fight tomorrow night.”

Canelo rejected any talk that he was the main culprit in the altercation. He claimed Jacobs was the one who initiated the physical antics.

“I see fear, and that was fear what he did there,” Canelo said through a translator.

“For me, and for my team and my people, it’s very important. We’re going to win tomorrow.

“I hope he tries [to win] but he won’t be able to.”