A British barman bluffed his way to ringside seats at the Conor McGregor “Fight of the Century” — and took selfies with a dozen Hollywood stars to prove it.

Fight fan Oliver Regis, 32, had bought a $2,500 ticket for the hotly anticipated bout but found his seat was right at the top of the T-Mobile Arena in Las Vegas.

The McGregor fanatic — who has a tattoo of “The Notorious” on his right leg — spotted the best seats in the house and managed to sneak past security.

He pretended to be with Floyd Mayweather Jr.’s security team and shadowed them past security — who he claims failed to scan his ticket, which would have exposed him.

Regis, from Stamford, Lincolnshire, about 90 miles north of London, then plunked himself down in the third row — right next to the ring during the bout before McGregor’s.

The barman told the Sun: “I did feel a bit cheeky — but this was a once-in-a-lifetime chance. I could not believe it worked.

“There were quite a few empty seats.

“I sat down in the third row and Mike Tyson then sat down behind me. LeBron James was on my row and I could see Leonardo DiCaprio.”

Not content with that, he then began asking the celebrities for selfies.

He added: “It was quite nerve-racking asking Tyson for a picture. He didn’t say anything — just nodded his head.”

But as the arena filled even more, Regis left his seat and began mingling with the celebs, CEOs and sports heroes.

He got pictures with Gerard Butler, Jeremy Piven, P Diddy, J.Lo, Demi Lovato, Eric Murphy, Jamie Foxx, Amir Khan, Chris Hemsworth and Floyd Mayweather Sr.

Single Regis, who has been to four out of McGregor’s last five fights, then took a seat in the 10th row — near English football legend Vinnie Jones.

The soccer player-turned-actor also agreed to a snap.

Regis watched the whole McGregor fight from the 10th row before sneaking out of the stadium.

He said: “My friends started texting me saying they had seen me on TV. It was very surreal, but it was the biggest fight in history!”

The Brit, who is enjoying a five-day break in Vegas with pal Alex Miller, 27, will return home to Stamford on Monday — and back to his job at the King’s Head.

He added: “I’m sure everyone will be talking about it when I go back. And I have the pictures to prove it!”