Dillian Whyte is returning to a "street guy" mentality to gain revenge on Alexander Povetkin and save his world title ambitions, says promoter Eddie Hearn.
Whyte was knocked out by Povetkin but they will collide in a high-stakes rematch on Saturday November 21, live on Sky Sports Box Office, with London's Wembley Arena and the Royal Albert Hall under consideration as venues depending on coronavirus regulations.
"If he wants to fight for a world title, everything is on the line in this fight," Whyte's promoter Hearn told Sky Sports News.
"In that sense, everything is on the line in his career.
"It was a big shock especially because he was controlling the fight. It was a brutal knockout.
"Whyte is so hungry to win. Many people think he's foolish taking the rematch so early. He thinks he should have won the fight, wants the chance to avenge the defeat, and wants to do it quickly.
"Povetkin said: 'I'm all-in, I knocked you out once and I'll do it again'.
"Whyte is raring to go. I've never seen him so motivated to win a fight.
"The bad boy in Whyte is coming out for this fight. Sometimes when fighters create success and gain wealth, do they become softer? I've seen another side to Whyte in the past three or four weeks.
"This is the old Dillian Whyte - that bad guy, that street guy who wants to do a job on Povetkin.
"This time, it's strictly business in an absolute must-win fight."
Povetkin took over Whyte's status as the mandatory challenger to Tyson Fury's WBC heavyweight championship.
Whyte has the opportunity to emphatically claim back that opportunity to challenge for a world title for the first time.
"We've gone from Whyte trying to win that fight to become mandatory to Fury, to him needing to win to save any chance he has of challenging for a world title," said Hearn.
"Povetkin is mandatory to Fury. The winner of this fight will be mandatory to Fury - it's just a case of when. Whyte had the date [by the end of February 2021] locked in and, if he wins, will be pushing for that date to be reinstated.
"But in my mind is victory only. The world championship fight will come. But if you lose this fight? Forget about that, sling it in the bin. You must beat Povetkin.
"We approach a fight with his world championship career on the line."
Oleksandr Usyk vs Derek Chisora is being targeted for October 31 and Anthony Joshua's defence of his IBF, WBA and WBO heavyweight titles against Kubrat Pulev is being targeted for December 12 at The O2 in London, it was confirmed by Hearn.