Oleksandr Usyk has been warned that his plot to become undisputed heavyweight champion will be ruined by Tyson Fury.
Usyk challenges Anthony Joshua for the IBF, WBA and WBO titles at Tottenham Hotspur Stadium on Saturday, live on Sky Sports Box Office.
WBC champion Fury can stay on course for a blockbuster battle against this weekend's winner, if he defeats Deontay Wilder in Las Vegas on October 9.
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"Usyk is not dreaming of becoming undisputed. He is planning it," his promoter Alexander Krassyuk told Sky Sports.
He also said: "The Fury fight has never been under discussion."
Joshua and Fury's talks to stage a summer mega-fight between the two reigning heavyweight champions to decide one undisputed king fell through but could be rectified if they emerge unscathed through their respective dangerous defences.
Usyk's potential to spoil those plans is being duly noted by Fury's promoters.
"I can't speak for Tyson, but I will certainly be watching Joshua vs Usyk," said Top Rank's Bob Arum who promotes Fury in the US.
"I've gotten to know Usyk very well because he's best friends with Vasiliy Lomachenko, and he's a wonderful young man and a great fighter.
"But I've said it before, and I'll reiterate this point - Tyson Fury beats any heavyweight in the world."
Ukraine's undefeated Usyk is bidding to become only the third boxer ever to win a world title at cruiserweight and heavyweight, after Evander Holyfield and David Haye.
He was the undisputed champion at cruiserweight after winning the World Boxing Super Series tournament.
Usyk has said about being significantly lighter than Joshua: "We'll probably find out in the first round which will prevail: power or skill.
"No, it doesn't annoy me [questions about size], absolutely not.
"Like I said, there's a lot people don't know, see or understand."
Joshua has said: "In my mind, I have removed the conversation that he is a cruiserweight.
"I get it. But I like to challenge myself. So I remove it out of the way. Let's look at where I'm at skills-wise and technique-wise.
"I've got what I already have - the strength."
Watch Joshua v Usyk on Saturday, live on Sky Sports Box Office, from 6pm. Book it via your Sky remote or book it online here. Non-Sky TV subscribers can book and watch it here.