The Mayweather vs. McGregor fight is going to be the event of the summer. Demi Lovato will sing the national anthem, and Sean “Diddy” Combs and Mark Wahlberg are going double-or-nothing on the winner.

Diddy and Wahlberg made a bet on the Mayweather vs. Pacquiao UFC fight in 2015, but now they’re back and kicking it up a notch with a double-or-nothing wager in “The Bet 2”.

RELATED: Drake Supports Conor McGregor At Floyd Mayweather Press Conference

Wahlberg is putting his money on Conor McGregor, and Diddy is once again backing his man Floyd Mayweather.

The fight is going to be a 12-round, super welterweight matchup between the MMA legends at the T-Mobile Arena in Las Vegas, and airs at 9 p.m. on Saturday, Aug. 26, on Showtime PPV.

Click to View Gallery
Mayweather vs. McGregor: Celeb Fans Take Their Corners