Paul and Tyson weigh in.

YouTuber-turned-boxer Jake Paul has screamed some fighting words into the microphone moments after his ceremonial weigh-in with Mike Tyson, moments after he was slapped across the face by the former world heavyweight champion.

Paul and Tyson both weighed in on Thursday at the Toyota Music Factory in Irving, Texas, with the two giving viewers a sneak peek of what is to come when they meet in the ring on Friday.

As Tyson strode across the stage, a clearly eager Paul, 27, popped up in front of the 58 year old, earning the YouTouber-turned-boxer a slap across the face.

The crowd in attendance gasped while Tyson had to be held back.

Paul, however, seemed unfazed. Instead, he blew kisses at the former champion.

“Talking’s over,” Tyson said, before exiting with his entourage.

In the moments after the slap, Paul said: “I didn’t even feel it.

“He’s angry. He’s an angry little elf.”

He added: “Mike Tyson, I thought that was a cute slap.”

The 27-year-old then launched into a series of expletive-laden remarks, promising to end Iron Mike in the upcoming fight.

“It’s personal now,” Paul added, before bellowing into the microphone: “He must die.”

Former world heavyweight champion Tyson (50-6, 44KOs) will step back into the ring for his first professional bout in 19 years at AT&T Stadium in the bout, which will be streamed on Netflix.

Tyson took part in an exhibition with Roy Jones Jr in 2020 but will be up against an opponent 31 years his junior on Friday.

Given the considerable age gap between the fighters, Paul has been installed as the favourite.

Tyson weighed in at 227.2 pounds (103kg), while Paul tipped the scales at 228.4 pounds (103.6kg).