Deontay Wilder has gone underground in a bid to conquer Tyson Fury in their trilogy clash.
The devastating puncher lost his unbeaten record and his world title to Fury when he was stopped in their rematch.
The heavyweight rivals are due to clash again on December 19 in Las Vegas in their much-delayed third bout.
Wilder has barely been seen or heard from since February as doubts swirled over his commitment.
But according to training partner Raphael Akpejiori, the giant American is in “amazing physical shape” after training in Miami.
“Based on what I know, the only person that can beat Deontay right now, is Deontay,” Akpejiori told Sky Sports .
“He will beat Fury if he sticks to the game plan from his coaching staff, and I know that he has all the physical tools. Right now he is in amazing physical shape, that I can tell you for sure.
“You will see a completely different Deontay, mentally and physically in the ring, when that bell rings again for that third fight.”
Wilder had surgery on his bicep after losing to Fury and has hinted he was injured before the fight.
And Akpejiori added: “You’re going to have to wait for Deontay to break it down and address those rumors [regarding his injury and fitness]. Listen, I can tell you from my conversations with Deontay that he was ready to fight Tyson Fury in July.
“The only reason why he didn’t fight Tyson Fury in July, was because the fight was moved due to the coronavirus pandemic and the lockdown that came after that.
“He does the same workouts that we’ve been doing. I don’t know how somebody can be injured and do all that. It’s really hard stuff, I can tell you that for sure.
“But concerning fighting Tyson Fury, he’s extremely confident. He’s very excited about that third fight. I can tell you for sure that he’s very hungry, and he’s trying to get back into the ring as soon as possible.
“He’s in great spirits, excited to get back to fight Tyson Fury.”