Eddie Hall and Thor Bjornsson almost came to blows less than a week before their grudge fight.
The former strongmen will finally clash in the ring in Dubai on Saturday night as they seek to settle their long-running rivalry.
But they crossed paths on Monday when Hall arrived at the gym as Bjornsson was leaving.
In footage shared online, the Icelander can be seen approaching his English rival and asks Hall if he is ready.
The pair square up as Bjornsson appears to put his hand on Hall's chest, prompting the shorter man to say, "If you touch me, I'll bite your f****** nose off."
Hall then claims his adversary looks scared before shouting, "Step outside and I'll tear your f******* head off."
Bjornsson replies: "Let's f****** go!" before Hall, who is being shepherded outside, responds: "You f****** p****."
Hall then appears to spit at Bjornsson who responds in kind before the Englishman is removed from the building.
The incident took place shortly after Bjornsson admitted he was keen to avoid his rival where possible ahead of stepping into the ring.
"Eddie's coming and as you guys know I really dislike the guy and I don't fancy seeing him," Bjornsson told fans on his YouTube channel as he filmed from the gym.
"If I can skip it I would rather only see him when I have to, I know we're about to do some interviews together in the next few days so I will see him then.
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"There's no need to see him sooner, I'm not excited to see him. Well, I'm really excited to see him on Saturday because I'm really excited to knock his teeth out."
Fans responded to the confrontation by claiming Hall appeared to be struggling with his confidence.
"A last desperate attempt to intimidate Thor," said one. "Eddie lost my respect a while ago but that was just a disgrace. Seems like Eddie is pretty nervous, he tried really hard to win the fight outside of the ring."
Another added: "Eddie lost the fight yesterday already, that was his last try to make something happen before getting KO’d."
