Fury escaped an astonishing upset defeat on Saturday when he climbed off the canvas to narrowly, and highly contentiously, edge out Francis Ngannou on a split decision. Former UFC heavyweight champion Ngannou was having just his first boxing bout when he took on Fury in a crossover event in Saudi Arabia.

It was a non-title 10-round bout, so Fury was never in danger of losing his WBC heavyweight championship. But his pride and reputation will have taken a severe dent ahead of the most important contest of his career.  Between them, Fury and Usyk hold all four of the major heavyweight world titles.

Usyk, like Fury, has never lost a professional bout. Since Usyk completed his second victory over Anthony Joshua last year to defend his unified championships, the clamour to see him fight Fury, the WBC heavyweight titlist, has continued to grow, even if that most unlikely boxer of all – Francis Ngannou – has inserted himself into the conversation after 10 unexpectedly competitive rounds. Fury did sign for the Usyk fight before his 10-rounder with Ngannou so likely saw the former UFC champion more as a tune-up bout than a competitive outing.

Usyk has been his ultimate target. They engaged in a high-profile war of words as negotiations for their bout started up in the early part of this year but then stalled.  Instead, Usyk defended his WBO, IBF and WBA belts against spirited British challenger Daniel Dubois in August and then Fury agreed to box Ngannou.

Once Fury emerged from the clash with Ngannou with a win, albeit a controversial one, he could confirm his showdown with Usyk. The two faced off in the ring in the immediate aftermath of the Ngannou fight. “Let’s go!” Fury said. Usyk said just the same. “Let’s go,” he replied. “I’m going to be fighting him, amazing.”

“Let’s go now if you want,” Fury continued. “It’ll be our next fight guaranteed.” There is no date set for it just yet, but it had been expected to be December 23, but that is now in doubt as Fury had a much tougher-than-anticipated clash with Ngannou. He was dropped and finished visibly marked up on his forehead, with swelling around his left eye. He will need to assess his recovery before confirming when he will be able to box next. It’s been two decades since boxing had an undisputed heavyweight king.

Lennox Lewis was universally recognised as the number one heavyweight in the world. After his retirement in 2003 the division was dominated by Wladimir and Vitali Klitschko. Together they did hold all four of the major titles at the same time but of course the two brothers would never fight one another.

Tyson Fury beat Wladimir Klitschko in 2015 to scatter three of the belts, while Deontay Wilder would pick up the WBC crown that same year. Fury was out of the sport for two years. Anthony Joshua then unified the WBO, WBA and IBF titles in an impressive championship-winning run. But he never fought Wilder when the American had the WBC belt.

It was Fury who came back in 2018 to beat Wilder. A clash between the two Britons when both were champions was never put together. Joshua subsequently lost decisively to Usyk twice. The significance of Fury-Usyk now being made is that on paper it pits the two top heavyweight boxers in the world against one another to decide the number one.

The simplest question for boxing – which for so long has not had a simple answer, has been: who is the true heavyweight champion? With Fury-Usyk set, the sport will finally get the answer it’s been waiting for. Only now it’s going to happen after an MMA fighter, in his first boxing bout, gave potentially the world No 1 what as he says was “probably one of my toughest fights in the last 10 years”. The path to undisputed, it seems, never was going to run smooth.