Andy Ruiz Jr has been labelled an "elephant" and a "disgrace" by Frank Warren after his failed world heavyweight title defence against Anthony Joshua.
After going down to a stunning defeat that shocked the boxing world against Ruiz in June, Joshua regained the WBA, WBO and IBF titles with a comfortable points victory in Saudi Arabia on Saturday.
Ruiz weighed in for the bout at 20st 3lb and conceded afterwards he had paid the price for "three months of partying", acknowledging he was overweight and should have trained better.
That situation in such a high-profile fight angered Warren, who manages undefeated former champion Tyson Fury.
"Andy Ruiz Jr brought disgrace to himself and the sport by simply failing to prepare to any sort of required level," Warren wrote on his website.
"Just because you are a heavyweight it shouldn't mean you don't have an obligation to display a certain degree of athletic intention.
"Yes, he was heavy last time around and usually wobbles a bit around the middle, but this was ridiculous.
"When eyebrows were being raised at the weigh-in he literally was the elephant in the room.
"Joshua must have wondered which chin he was supposed to aim for. It is a bit late after the event to come out and say you partied too much and regret carrying so much weight."
Warren explained that in a typical fight where promoters and TV bosses were not hoping for a particular result, there would be anger if a fighter turned up short of peak condition.
He went on to add: "Spare a thought for those punters who might have had a punt on the champion, who had every right to believe he had put the graft in having had the benefit of a full camp.
"Professional athletes have a responsibility to ensure a level playing field on behalf of those who pay for the privilege of watching.
"What we ended up with was a fella who basically scoffed himself out being world champion and a spectacle that suffered as a result. The fault for this lies firmly with Ruiz.
"The bottom line from what we saw over in Saudi is that Ruiz was a disgrace to the belts he was defending. He did a Buster Douglas and ate himself out of contention.
"I saw an interview before the fight with Ruiz saying he had achieved his dream. Well, if his dream was to win the titles then stuff himself stupid and lose them at the first time of asking, then his dream has become a reality.
"King of the heavyweight division to Burger King in the space of six months."
Fury is due to face WBC champion Deontay Wilder in February, a rematch after their dramatic draw in December 2018.