Oleksandr Usyk has warned Tyson Fury that his father John headbutting one of his friends has given him increased motivation to win their fight on Saturday – and that he is surrounded by professional soldiers.

The build-up to the undisputed heavyweight title fight between Fury and Usyk has already been marred by Fury’s father John, under little provocation, headbutting Usyk’s friend Stanislav Stepchuk when the fighters’ respective entourages crossed paths on Monday in Riyadh, Saudi Arabia.

Saturday’s fight at the Kingdom Arena already had the highest of stakes – it will likely define both fighters’ fine careers more than any other – and, according to the 37-year-old Usyk, typically the most composed and disciplined of champions, John Fury has given him further cause to win.

There have been times Tyson Fury, 35 and the WBC champion, has appeared frustrated when his attempts to unnerve Usyk haven’t brought success, and Usyk – the IBF, WBA and WBO champion – who has previously spoken so admirably of his experiences of being on the frontline in Ukraine while it attempts to resist Russia’s invasion – even said that he intervened to prevent those around him from retaliating.

“If they want to destabilise my team, it’s not possible,” he said. “Because I don’t just have professional coaches and trainers – I have professional soldiers.

“The security were calling ‘Back Team Usyk, back!’ My team is very good at wanting to fight – not boxing – street fighting; shooting; knives; wrestling. 

“But I said ‘Hey, hey guys, get back’. We had to behave properly. The situation doesn’t matter to me, it’s just more motivation for my team.

“For me it doesn’t matter. It’s just bad behaviour from Tyson’s team. We are professional athletes, not street fighters, and this is a big event for our people, the UK and Ukraine.”

After headbutting Stepchuk, one of the smallest members of Usyk’s entourage, John Fury left with blood pouring from his head, and Stepchuk left largely unscathed. 

“My friend did not bleed because he is a powerful guy,” Usyk said. “He is a street guy. Did you see the video? He was like a Pitbull, ‘ruff’. I said ‘Stop!’ and they said ‘Okay’. He’s only my friend – it’s a secret who the soldiers are in my team.

“It’s bad; it’s just bad. A stupid situation. I don’t want to call John bad because I don’t know him or his mind. But he hit my friend, my team, and it’s just another reason for me to win.”