Dillian Whye believes that Deontay Wilder made "the worst mistake of his career" when he parted from co-trainer Mark Breland.
Wilder reacted with visceral anger when Breland threw in the towel on the former WBC heavyweight champion’s behalf in his second fight with Tyson Fury.
The pair are set for a third fight, but Bob Arum and Frank Warren both believe that it will be difficult to set the event before the end of 2020.
Wilder is believed to be keeping on his other trainer, Jay Deas, as he prepares for his third fight. However, Whyte thinks it was an error to let Breland go.
Speaking to Sky Sports, the former WBC interim champion said: "I think it's the worst mistake he's ever made, because Mark Breland is the only person in his team that actually was a boxer and actually was a world champion. He was the only person that didn't care about money or fame.
"Someone who was actually from an emotional point, someone who understands, thinking about his health and did the right thing by throwing the towel in, because he could have got seriously hurt.
"He was getting hit with punches that weren't knocking him out, they were concussing him. Mark Breland knows what it's like, because Mark Breland has been in the same position Wilder was in. He's someone that cares about the athlete and the boxing side of things.”
Whyte believes that Breland was vital to Wilder’s camp because he was not a yes man.
“‘Not just 'Bomb Squad', nonsense,” he explained.
“He doesn't care about that. He's the only one in the team, you don't see him running around and shouting and screaming. He's just a little quiet guy, does his job.
"Deontay Wilder is an idiot, he clearly can't see it. Good luck to him, it's his team, he can do whatever he wants. But I think it's a bad mistake. Mark Breland is the only one that knows boxing in his team."
Whyte is set for a 21 November rematch when he faces Alexander Povetkin.