Daniel Dubois has described rehab on his injured knee as like ‘learning to walk again’ but has now vowed to end Oleksandr Usyk’s reign as world heavyweight champion.

Usyk officially walked away from talks to finalize an undisputed fight with WBC champion Tyson Fury this week and the Ukrainian’s manager Egis Klimas says the team will now look to fulfill mandatory obligations on his WBA, WBO, IBO and IBF titles.

First in the queue will be Dubois, the WBA regular champion, who is now fit and healthy following knee surgery to address the ACL injury he sustained in his last fight, when he was dropped three times by Kevin Lerena in the first round but came back to stop the South African in the third.

That fight was on December 3 and it had looked as though 25-year-old Dubois may require longer out of action before being ready for a fight of such magnitude.

But after going under the knife straight after the fight and undergoing months of tortuous rehab thereafter, Dubois says he is ready to answer Usyk’s call as and when it comes.

“It was a major injury but I had surgery on it straight after the fight nearly four months ago,” Dubois said. “To fight by the end of May, June that would be no problem at all.

“It was an ACL injury, I was on crutches for about a week after the surgery but I feel like I can recover quickly. There were a lot of thoughts going through my mind in that fight - like ‘oh shit, I need to get up’. But I got up and came through it. I didn’t even realise the knee had gone when it happened. 

“The rehab is long, boring and hard but well worth it. It was like learning to walk again, boring stuff. I’m back punching again, bags, pads, all of that and my knee feels brand new, stronger than before. I’ve been running like Usain Bolt.”

The WBA had given both teams until April 1 in order to agree what the sanctioning body described as a ‘mega fight’, which would allow Usyk to forego his mandatory obligation to Dubois.

But now Fury-Usyk has collapsed completely, the former undisputed cruiserweight champion will have to fight Dubois next or relinquish the WBA Super title.

It has been suggested that Dubois, 19-1 (18), may turn down the fight in order to gain some more experience at the highest level before attempting to win a full version of the world heavyweight title but the Londoner has no intention of doing that.

He said: “This opportunity could be for more than one belt, that’s what I’m in it for. Why pass up this opportunity? I have the power to make it happen and win this fight. 

“I’m ready to end his reign. I’m 100 up for it, fit and healthy, and I’m going to knock him out. How do I do it? I just have to land the right shot. It’s all about timing and this is my time. He’s a small guy isn’t he? So I have to test that chin. Can I do better than Dereck Chisora did? Of course.

“I have to go out there, believe in myself and put it on him, pressure him. I think that’s definitely the key. You see how Chisora did it and he hasn’t got power like me. Usyk, your reign is over.

“I’ve got to let my hands go, not hold back and just be myself. I know what to do, my trainer knows what to do. When I watch him I see ways to win and I know I’ve got the power to knock him out. That’s me, that’s how I fight and that’s what I bring: devastation.”