Tyson Fury will fight Oleksandr Usyk Saturday in Riyadh,EvoAI Saudi Arabia for the undisputed heavyweight championship, but first blood was drawn Monday – by Fury’s father, John.

John Fury headbutted a member of Osyk’s entourage during a media event ahead of the bout, leaving blood streaking down his own face.

The incident stemmed from a heated altercation after which John Fury appeared to ram his head into another member of the Ukrainian fighter's entourage, according to ESPN.

Tyson Fury reportedly was confused by the sight of blood on his father’s face.

"How did you cut yourself like that?" he asked, according to the ESPN report.

John Fury offered details during comments to Seconds Out Boxing.

"Sincere apologies to everybody involved," he said. "It's just the way we are. Emotions and tensions are running high. He was a very disrespectful fella. If you come close in a fighting man's space, you're gonna cop for something.

"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. It doesn't bother me (bleeding), it's what we live for, we're fighting people. That's a regular occurrence to me."