Tyson Fury will be a far tougher test for Deontay Wilder in their rematch, believes promoter Frank Warren.
Fury was denied victory by the judges last December when they scored his first fight the world champion a draw.
Since then Fury has knocked out Tom Schwarz and on Saturday takes on Otto Wallin back in Las Vegas.
He has retained his slimline shape which he achieved by losing almost 10 stone last year.
Fury is due to challenge Wilder again next year and Warren said: “He will be in much better shape than he was the first time around.
“That time he was basically training to make weight rather than training for the fight.
“Anything can happen though, we saw what happened with Anthony Joshua against Andy Ruiz.
“Even when Tyson fought Wladimir Klitschko, he was a big underdog in that fight, so anything can happen with these big guys. He cannot take his eye off the ball at all.
“Tyson is doing what he needs to do and that is stay busy.
“He needs to stay active so he doesn’t put weight on, mentally he needs to be on the money too.
“He is going to be more dangerous than ever.
“This is Tyson Fury with 18 months behind him in the gym rather than a six-month crash course.”
Fury is having his third successive fight in America as he bids to build a fanbase across the Atlantic.
And Warren believes his profile is now bigger than Anthony Joshua who lost to Andy Ruiz Jr in June.
“Now Fury has built up his profile on ESPN, he has a bigger profile than Joshua has got in America,” he added.
“First of all he has got a big personality.
“He has been involved in the big fights. He went to Germany to fight Klitschko and he went to America to fight their champion. That sums him up.
“Joshua took a long time to go to America and when he went he was going to fight Jarrell Miller and then he picked Ruiz. In both of those fights he was a huge favourite.
“Fury went and fought the best American heavyweight out there, that says something about him.”