Tony Bellew, the former opponent of OLEKSANDRUSYK in Ukraine, said that OLEKSANDRUSYK is the "best boxer Anthony Joshua will ever meet".
The former undisputed champion in cruiserweight will face AJ at Tottenham Hotspur Stadium, September 25.
Joshua wants to keep his three world heavyweight titles
Bellew was stopped in round eight by Usyk back in November 2018. She warned Joshua about the amazing skills that the 18-0 man has.
TalkSPORT spoke with him and he stated that Anthony Joshua would be facing the greatest boxer of his career.
"Oleksandr Usyk, when it comes to pure, natural boxing, is the best natural boxer Anthony Joshua will ever meet." He's amazing at what he does."
After beating Bellew three-years ago, Usyk was promoted to heavyweight. However, he has only fought twice since then.
After a routine win over American Chazz Witherspoon he was then tested against the all-action Derek Chisora in the blue-riband section.
Although he had to deal with some difficult moments, Usyk won a unanimous victory.
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He won the WBO mandatory Joshua slot and now has his chance.
Bellew thinks Usyk could be taking the fight to AJ too far.
Bellew said that Usyk is not a true Heavyweight. Bellew said, "Everyone keeps going on. Yes, he's a cruiserweight but he's the greatest cruiserweight to ever put on gloves.
"He does have an incredible skill set. But I think that weight divisions in boxing exist for a reason.
"Come round seven, eight, and nine, he will discover why he's not a true Heavyweight."
"I believe that Anthony Joshua's speed and power, as well as his perseverance will catch up to Oleksandr Usyk.
"I wish he would stop battling my friends because I want him to be supported!" He is a great admirer and I have so many respects for him. But he keeps fighting my friends so that I don't support him.
If AJ succeeds, he will be able to stage a clash with Tyson Fury (British) who currently holds the WBC title.
This is assuming Fury can defeat Deontay Wilder in their trio clash on October 9
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