The length of a beard, kissing a cross, or who won a staredown seem such minor issues that arguing over them appears to be nothing more than petty.

But Oleksandr Usyk and Tyson Fury are the two greatest fighting heavyweights in the world today. And when it comes to their rivalry they want to win on every score.

Fury had never lost as a professional boxer, until he met Usyk in Riyadh earlier this year. That thunderous fight in May decided the first undisputed heavyweight champion in 25 years and the first of the four-belt era.

It was Usyk who won a split but compelling decision and secured his place in the history books.

Fury now wants to reclaim the WBO, WBC and WBA world titles, in their Sky Sports Box Office rematch on Saturday night. He wants to show there is no man out there ultimately who has the beating of him, and he wants to extend his own legacy – establishing himself as the unquestioned master of the comeback

So then what does a beard matter?

The argument, ostensibly, was about whether Fury’s full beard could cushion the force of a blow or interfere with the trajectory of a punch. That is conceivable, but when you consider Usyk has now bulked up to heavyweight and hurt Fury so badly in the first fight only the ropes, in their famous ninth round, prevented him from crashing to the canvas, it is unlikely to be a problem for the great Ukrainian.

The argument is about something more. It’s about Usyk’s team wanting to strip an element away from Fury. The Briton has gone into what he describes as “beast mode” for this training camp. His entourage has been reduced, Fury closeted himself away in Malta for his preparations barely speaking to his wife and family.

For this week in Riyadh, dressed in a leather jacket and with the beard, Fury has been belligerent and almost unapproachable to those outside his circle. He is coming for the “war” he threatened at the weigh-in.

He wants to beat Usyk out of the heavyweight division so that he goes back down to cruiserweight. “He’ll need to,” Fury told Sky Sports. “I’m going to bash him up really badly.”

This version of Tyson Fury, even more menacing than before, should be an improved fighter.

“You’re going to see a better one this time I believe for sure. I believe I’m definitely going to be better than last time and I don’t have to be a lot much better because it was a very nip and tuck fight,” he said.

The first fight was finely balanced. Back in May Fury seemed to revel in a heavyweight contest of the highest calibre. Animated for his walk in, he showboated in the ring and insisted he thrived on the atmosphere.

“I enjoyed all the fight. The occasion. The being in the ring. Great entrance, great entertainment. Overall I thought it was a fantastic performance from myself. Even watching it back I thought it was a great performance. I’ve had some good performances and I know I didn’t get the W. But I still thought it was an excellent performance by myself. From 1 to 10 how I thought I performed, I thought I performed a 10,” Fury insisted.

The showboating then could well have been an error. He was doing it to show how good a boxer he was, to try to offset and bewilder Usyk and perhaps even to buy himself space and breathing room.

It was a façade, a trick, that Usyk did not fall for. He stuck to his work. Took his licks, painful ones too over the first half of the fight, and just as he had promised he would, did not leave Fury alone.

But eliminating that, with more application and defensive tightening, could make all the difference. Even though the Briton thought it was the best he’d boxed in years, he needs to make some vital adjustments for the rematch.

“Sometimes you look at a fight and I think I didn’t perform good, I could do better next time if I did that, that and that,” Fury said.

“But for that way of boxing I don’t think I did anything wrong. I thought I did an excellent performance and I know that I’ve seen reports saying Tyson’s fell backwards, he’s on decline and this that and the other but I didn’t show it in that fight if I am.

“I thought it was probably the best performance that I’ve had in the last five years. Since Wilder II for sure and that’s almost five years ago.”

It should be dispiriting to think that he boxed almost as well as he has ever has, and yet still suffered his first defeat. That shows how good Usyk is. But Fury seemed strangely energised by the challenge of facing him again.

If Usyk’s team wanted to strip the beard, the persona Fury has adopted, from their opponent, the Briton’s team looked to remove a source of inspiration from their rival.

During the first fight, under intense pressure with the contest heavy and hard going, Usyk sat in his corner between rounds, looked to the heavens and kissed a cross.

Usyk told the media this week: “This cross was a present from the chief monk in one of the Greek monasteries, where I go. This cross gives me strength and leads me to victory.”

Whether it was the cross leading him, or his own spirit he excelled and carved out a path to victory.

Of course, it only takes the wrong camera angle and an unknown object being pressed to a fighter’s lips to fuel speculation. Thus, Fury’s team argued, any cross kissed in Usyk’s corner should be taken away for testing to negate any suspicions.

That may well be a reasonable point. But that dispute still hinges on a small item, something Usyk wants and something Fury’s side doesn’t want him to have.

These are just the early skirmishes ahead of the championship contest, and the fight won’t be decided on them.

Usyk of course has other sources of inspiration. He is devout, his country’s flag is carried with him and he is proud to represent his people. The memory of his father, who never lived to see him become a world champion, also propels him.

“Of course he’s present. It could never be any different after all he did for me. But now he comes to me less in my dreams, or he practically doesn’t come at all, because I said so that he shouldn’t,” Usyk said of his father.

“But maybe he will appear closer to the fight. But I remember him, I often think about him, I look at his photos. He’s always with me. I think he’s still with me, he’s sitting somewhere, maybe he’s sitting behind this guy so you can see me better.”

Usyk always holds himself apart. He is a man who’s hard to read, who engages certainly but always on his terms. Fury likes to entrap opponents in psychological games, yet Usyk is the only one who never seems to play.

The Ukrainian strives to better himself. He revealed something of his mindset when he told Sky Sports: “Life goes in cycles. You either try to live justly and do the right thing, or you don’t and end up being a nobody.

“We’re all flawed, we’ve all got issues. To some degree we’re all vicious. But some of us at least try, we reach for something better. For God. While others don’t even bother.

“Here’s how I’d put it. A bee doesn’t need to prove to a fly that honey is better than garbage. But the fly will always argue that garbage is better than honey.”

He opens up something of himself, but it feels too like the real Usyk is something well hidden behind riddles.

While the battle of skill, technique and physicality between them can only take place within the allotted 12 rounds of their fights, the battle of wills has extended from the last bout all the way to this.

That was exemplified in the extraordinarily protracted staredown both men locked into after the final press conference.

It started out intense, it went on so long it began to feel absurd, and then stretched even longer until it became magnificent once again.

You wondered what they saw when they gazed at each other. They certainly didn’t see the nervy crowd of men around them who were wondering how to intervene, how to break the two apart without offending either fighter or triggering an escalation that couldn’t be contained.

They didn’t see themselves in each other. Both men are utterly contrasting characters, even if their pride and hostility is underpinned by a rarely articulated respect for their rival.

They can’t have been seeing the future or Saturday night’s fight. If their minds had been elsewhere it would have been easy eventually for one to turn aside and move on.

Instead they must have seen only that moment. Suddenly each had decided that he would not be the one to break, to look off first or falter. So they stared and they’ll still be glaring into the image they see of one another from now till the fight and for as long as it lasts, until they see themselves at the end of it.

Oleksandr Usyk and Tyson Fury’s huge heavyweight rematch will be live on Saturday December 21 on Sky Sports Box Office. Book Usyk v Fury 2 now!