Eddie Hearn, promoter for Anthony Joshua, feels confident that his boxer can turn back the tide to get revenge on Andy Ruiz.
On June 1, Ruiz stopped Joshua in seven rounds to capture the IBF, IBO, WBA, WBO heavyweight titles at Madison Square Garden in New York City.
During the contest, Joshua was knocked down four times before the contest was waved off.
A rematch is being planned for the fall, with Joshua executing a rematch clause.
Ruiz was a massive underdog in the first bout, but a lot of experts are now picking him to win the rematch.
Hearn admits he will be very nervous when the second fight takes place.
"I saw Ruiz the other night saying he’s got to run in the rematch – that’s what he can’t do," Hearn told IFL TV.
"He can’t run, he boxed off the back foot last time. But it’s going to take a really good performance, physically and mentally, to win this fight. I just believe in him. I believe in his mindset, I believe in his ability, and I just believe that he’s going to do it.
"Honestly I think it’s just a case of, and he said it to me the other day, 'People just talk to me about Wilder.' All fight week was, 'After this fight, I’ll sit down with Wilder, Fury' all this. So subconsciously it’s like this fight is won, and when it breaks down or it goes wrong or you get hurt, it’s like, what the f***? But this time you can go in with the attitude that this is everything, and that’s what he had when he went in against Klitschko.
"He was prepared to go to any lengths to win that fight, just that fight, it was the only thing that mattered to him. And now we’re there again with Ruiz. This is going to be epic. But it’s going to be a real tough fight. I can’t wait. I’m going to be absolutely sh*ting myself, but this is what we live for."