Oleksandr Usyk (left) has reigned as the undisputed champion at cruiserweight and heavyweight
Unified heavyweight champion Oleksandr Usyk believes Anthony Joshua will beat Tyson Fury and has been helping him come up with a gameplan for the all-British contest.
Joshua returns to the ring on 25 July to face Kristian Prenga in Riyadh, Saudi Arabia, and has signed a deal to fight long-term rival Fury later in the year.
The 36-year-old has been training with former opponent Usyk in recent months, spending time with the two-time undisputed heavyweight champion in Spain and Ukraine.
Undefeated Usyk, who has beaten both Joshua and Fury on two occasions, told BBC Sport: "In my opinion AJ wins against Fury.
"Fury is an unbelievable fighter and Fury is a very dangerous guy but I look how Anthony works and how he has changed.
"I like Fury, he is my greedy belly best friend, he's an amazing fighter but I want Anthony to win - he deserves it."
Usyk does not foresee Joshua encountering any issues against Prenga in what he calls "official sparring", but has been advising him on how to overcome Fury.
The Ukrainian is preparing to defend his WBC title against Rico Verhoeven on 23 May in Egypt and will welcome Joshua into his camp over the next couple of weeks.
"We will help him in training," Usyk said.
"We speak about strategy, boxing skills and psychology. We speak about fights, our fights, and I say 'champ, come on, don't stop'."
Joshua's last fight was a routine victory against YouTuber-turned-boxer Jake Paul in December, but he has taken some time away from the sport to recover mentally and physically after being a passenger in a fatal car crash later that month that killed two of his friends.
Usyk said he could empathise with Joshua because he has lost friends during the ongoing conflict in Ukraine following the Russian invasion.
"I said 'listen, God gave you one more chance. Take this chance and don't stop or cry. This is life, pray every day and god will help you. Whatever you need I will help," Usyk said.
"It's hard but I think my friends now are like angels.
"Every day I pray for these guys - this is life. I don't know what waits for me and my team tomorrow, but I continue to work, pray and help.
"If God gives you a gift every day then appreciate it. It's hard but you must continue to live because God gives you that."