Deontay Wilder and Tyson Fury will be prevented from taking part in the traditional eve-of-fight faceoff at Friday's weigh-in for their heavyweight title battle in Las Vegas.
Promoters for both boxers have backed a decision to call off the familiar confrontation amid concerns it could turn nasty.
A news conference Wednesday descended into rancor as Wilder and Fury shoved each other before being separated.
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The Nevada State Athletic Commission (NSAC), which regulates fights in Las Vegas, decided the moment was a clear sign Wilder and Fury should not risk further altercations before getting into the ring.
NSAC executive director Bob Bennett told ESPN: "The reason the decision was made, on behalf of the commission, is because the press conference spoke for itself.
"The actions of the two fighters pushing each other, which was not staged, is not indicative of the image of our sport as a major league sport, thus having a faceoff is not in the best interest in the health and safety of the fighters, the public and the event.
Well, sh*t almost got real physical between Wilder and Fury to kick off today’s press conference. 👀#WildervsFury2 pic.twitter.com/OPzF1UAwxW
— Andreas Hale (@AndreasHale) February 19, 2020
"And, quite frankly, that image, where you have two professional athletes pushing each other where somebody could get hurt, is not keeping with the image of a major league sport and we're a major league sport."
Bennett said he told promoters Tom Brown and Bob Arum of the decision and neither man opposed the move.
Arum told ESPN: "If this fight depends on a faceoff to sell it, we have not done our job."
On the other hand, Frank Warren, who co-promotes Fury with Arum, told metro.co.uk: "It's a stupid decision. The faceoff is traditional."
The fight at the MGM Grand is a rematch after a thrilling draw in December 2018. Wilder's WBC belt will be on the line.