A man in London picked the wrong place at the wrong time to stir up trouble.

Julius Francis, a 57-year-old former professional boxer who was once the British champion and in 2000 fought the legendary Mike Tyson, is now a security guard at Boxpark Wembley, the NY Post reports.

In a video that circulated social media on Tuesday, a man in a blue durag is seen repeatedly yelling obscenities at the security staff and other people who appeared to be workers at the venue, saying “f*** you!” too many times to count, and yelling, “I’ll f*** you up!”

The man shoves multiple people as a group of security guards try to nudge him away from a set of guardrails around the space.

About 45 seconds into the clip, Francis unleashes an absolutely vicious right-hand, knocking the rabble rouser down with one of the most severe head-shots you’ll ever see.

“Police are aware of footage circulating on social media showing an incident involving security staff and a member of the public outside Boxpark in Wembley,” the Met Police said.

“An investigation into the circumstances, including to establish the identity and welfare of those involved, is under way.

“There have been no arrests and inquiries are ongoing.”

A spokesperson for Boxpark added: “Our team are aware of footage being shared online.

“This incident is currently under review and part of an ongoing police investigation, and therefore we are unable to comment further on the incident at this time.

“We would like to stress that the safety and welfare of our customers and our staff is our number one priority.”

The video registered more than 6.1 million views on Twitter in less than 12 hours.

Facing Tyson in 2000, Francis fared only slightly better than his foe in this video. Not even a minute into the second round, Tyson won by TKO.

Nonetheless, should anyone have an inclination to start some trouble at Boxpark Wembley, this video should dissuade that idea.