Queensberry promoter Frank Warren has had quite the journey with his charge Tyson Fury as he approaches the first undisputed heavyweight title fight in 25 years. The pair’s working relationship spans more than a decade.

“In the early days, when he fought Derek Chisora for the second time [in 2014], it was a WBO final eliminator,” Warren told BoxingScene. “The winner was to get [Wladimir] Klitschko. Going into that fight, I fancied Chisora. He was coming off a stream of very good wins against top-10-rated fighters, but Tyson just did a job on him. He didn’t win a second of any round – so much so that I stopped the fight. 

“I said to Tyson immediately after that fight, ‘You will beat Klitschko.’ He showed a completely different dimension to what he was capable of, and he did go out and do a job on Klitschko, who was the best heavyweight of his generation. He gave him a boxing lesson in his adopted backyard of Germany with 54,000 people there. We had a couple of problems in the Klitschko fight with his management. The fight went to Germany when I wanted to do it in the U.K.”

What followed saw Fury turn his back on boxing despite his surprise achievement to become the heavyweight world champion. 

“He vacated his belts,” Warren explained. “He was never stripped of any of them, which gave [Anthony Joshua] the chance to challenge Charles Martin. I’m not going to go into what they were, but there were problems with his team that sent him into a downward spiral. It’s well-documented. He was boozing and doing things he shouldn’t be doing, and he got to a stage where he was suicidal. I heard some of the stories. I wasn’t aware of how bad it had gotten – for example, that he was suicidal. When we met, he was probably about 10 or 11 stone over his fighting weight. He was huge! But I could see in his eyes what I saw when I made the fight with Derek Chisora.

“Tyson having those suicidal thoughts sought help and he was diagnosed as being bipolar. He overcame his demons, we worked hard to come back together, sat down and worked out what we were going to do. You could see that boxing gave him a goal in life. He’s worked hard to change all aspects in his life and he’s turned it around. I think people appreciate it; I think some journalists don’t. They don’t seem to know what bipolar is. Go on the NHS website and it will show you the symptoms. Sometimes it’s something you might say; but his actions, he’s never been in any trouble with anybody. He's an absolute proper professional. It all culminated in being here two days before the fight.

“Then we decided we wanted to go to America, and part of that was to work with Top Rank, who are the best, and with Bob [Arum]. We did the first fight in America with Al Haymon because Deontay Wilder was with him. It was a bit of a dodgy decision [a draw], but it was what it was and Tyson showed what he was all about there.”

WBC titleholder Fury (34-0-1, 24 KOs) will collide with IBF, WBA and WBO titlist Oleksandr Usyk (21-0, 14 KOs) Saturday in Riyadh, Saudi Arabia – a far cry from what happened in 2016.

“I'm repeating myself continuously,” Warren added. “This is the biggest, biggest boxing event of the 21st century. It’s history in the making; there hasn’t been a unified heavyweight champion in this century – four belts on the line, instead of three in the last century. It’s two undefeated fighters at their peak; they are in their 30s at their peak, and somebody’s 0 has got to go. On Saturday, we are going to find out who the biggest and baddest man on the planet is. 

“Anything can happen in boxing, but I believe Tyson will win and he will stop Usyk in an exciting fight. Usyk is not coming to make up the numbers. He’s got an impeccable record and [was] a gold medalist at the Olympic Games. He’s the best cruiserweight of his generation. He’s been a heavyweight now for four and a half years and done everything that is asked of him. He’s beaten big guys; he beat AJ twice. I think we are going to witness something special.”

Fury comes off a narrow points victory over Francis Ngannou last October, with Usyk dispatching Daniel Dubois last August. Both men showed weaknesses.

“You look for chinks in boxer’s armor,” Warren continued. “They will be looking at the fight with Ngannou. He had a really off night – a bad night at the office – but had a bad night at the office and won. That’s what great fighters do. 

“He’s in his second camp for this camp and peaked at the end of his sparring. Then he got the cut, obviously the fight got postponed. He now has the benefit of going into the fight much fitter than he would normally go into a fight. You see the result of that this week – he is ultra, he is a little bit cut, and he is glowing. He’s in a great place mentally, which is really important for him.”