Former British heavyweight champion Dillian Whyte accused Anthony Joshua of lacking ambition after he lost his heavyweight titles in a crushing defeat to Oleksandr Usyk.
Usyk claimed a stunning unanimous decision win at Tottenham Hotspur Stadium after the judges scores of 117-112, 116-112 and 115-113 confirmed a dominant victory.
"I said if Joshua tried to box he was always going to lose," Whyte told BBC Radio 5 Live.
"If he had come out and bullied him and pushed the pace and let his hands go he could have knocked him out in the first even round.
"But he came out and was being too negative, he seemed like a gun-shy fighter. You are the bigger man, have a go.
"I don't know, he lacked ambition in the ring there tonight.
"The first round, Usyk landed the first strong blow and Joshua was a negative fighter. He got tagged with a left and he was worried the whole time."
Whyte will next face Otto Wallin on October 30 at the O2, but vowed he would have a "shoot-out" with Usyk if ever given an opportunity.
He added: "I have to go through Wallin first, after we will see.
"But I tell you what, I will not be losing to an overall decision like that, I can tell you that now.
"I will go out and I will have a shoot-out - if I get knocked out, I get knocked out, but I will have a shoot-out, I am not getting out boxed over 12 rounds like that, no chance."
Joshua's promoter Eddie Hearn said the camp were "gutted" at the defeat and admitted Joshua got the fight wrong.
"We have obviously been here before, but this time we are here against a pound-for-pound great fighter," Hearn said.
"The (Andy) Ruiz defeat was difficult to take because it was a shock to the system.
"This is one we knew could happen if he didn't get it right, and he didn't get it right.
"I don't think AJ boxed a great fight tonight, Usyk boxed an excellent fight.
"It was all the things we worried about in the fight before, the over-thinking, trying to stand and box with him, and he took too many shots early.
"Usyk went through the gears and was a bit more aggressive than I thought he was going to be. He was the deserved winner tonight."
Usyk well worth victory
Carl Froch, the former super middleweight world champion, believed Usyk was worth his victory.
He said: "All the boxing purists who know the game, we always knew Oleksandr Usyk could outperform AJ, outbox him and beat him on points.
"I don't think any of us knew he could do it in such a manner. Towards the end, he took control, then started to beat him up when he didn't need to.
"That was a boxing match and a proper fight, which in the end Oleksandr Usyk was in control of. He deserves every credit.
"Anthony Joshua did his part, he tried to box with him and work the body at times, but it wasn't enough, he simply wasn't good enough."
Former lightweight champion Anthony Crolla heaped praise on Usyk.
"AJ has brought some of the most special nights in British Boxing history. Tonight he lost to a very special fighter. A once in a lifetime fighter," Crolla wrote on Twitter.