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Tensions are heating up between the camps for Tyson Fury and Oleksandr Usyk ahead of Saturday's clash to crown the first undisputed heavyweight champion of the four-belt era. The situation reached a boiling point when Fury's father, John Fury, delivered a headbutt to a member of Usyk's team on Monday in Riyadh, Saudi Arabia.

As the two teams chanted their fighters' names at one another, the elder Fury began to step into the faces of various members of Usyk's team before delivering a headbutt to Stanislav Stepchuk. As he was pulled away, Fury had blood streaming down his face from a cut on his forehead.

Fury spoke to Seconds Out after the incident, apologizing and stating that Stepchuk had been disrespectful.

"Sincere apologies to everybody involved to be honest with you," Fury said. "It's just the way we are. Emotions and tensions are running high. He was a very disrespectful fella, wasn't he?

"If you come close in a fighting man's space, you're gonna cop for something, aren't you? People don't understand we are the real deal as fighters. What matters to me is respect for my son and he wasn't showing any of it. He mentioned my son and that was it, so he had to have it."

In his own interview with Seconds Out, Stepchuk claimed he had not done anything other than chanting Usyk's name and that he didn't touch Fury before being struck with the headbutt.

WBC champion Tyson Fury meets WBO, WBA and IBF champ Usyk on Saturday in a pay-per-view main event. It is arguably the biggest heavyweight fight in decades and one that was supposed to take place in February before Fury suffered a cut in training, forcing a late postponement.