Tyson Fury believes Anthony Joshua has a confidence problem and claims he could knock out his heavyweight rival inside two rounds.
A unification fight is potentially on the cards this year between WBC champion Fury and Joshua, who holds the WBA, IBF, WBO and IBO belts.
Speaking after beating Kubrat Pulev last month, Joshua said he wanted to take Fury's "head off his shoulders", but Fury does not believe his rival's bravado.
"I don't believe he's as good as people crack him up to be, or he doesn't believe he is in his own self," Fury said on Sky Sports.
"He's got a confidence issue. He's coming off two shaky performances and boxing is all about who is in form and who isn't.
"On his last two fights, he's not in form. On mine, I am, so momentum is with me and I just believe take him out early, very early, maybe even one round or two rounds."
Fury is optimistic the fight, which would be one of the biggest in British boxing history, will take place as soon as is practically possible.
"Hopefully we get to go one-on-one combat with not only the two best heavyweights out there but two heavyweights who are in their prime and not past it.
"Whenever the world gets back to normal, whatever normal may consist of after this pandemic, then that's when this fight is going to happen," he added.
"This fight has been brewing for a long time. They've been avoiding me for a long time and now it's finally got to happen.
"They either run away from the fight and announce it publicly or they take the fight. Either way it's a lose-lose situation for him."
Fury believes there is an imperative for the fight to happen sooner rather than later, comparing the bout to the one between Floyd Mayweather and Manny Pacquiao that finally took place in 2015.
"Boxing is one of those sports where rarely do you see the best fight the best," said Fury. "It's always the champion picks his opponents and you never get the two top guys fighting each other.
"We saw the Mayweather-Pacquiao fight, we were waiting for that fight for 10 years. When it finally happened, I believe Pacquiao was past his best. It maybe should have happened four or five years earlier.
"So hopefully we get to go one-on-one combat with not only the two best heavyweights out there but two heavyweights who are in their prime and not past it."