Unbeaten boxer Floyd Mayweather will fight UFC lightweight champion Conor McGregor in a much-discussed boxing match on Aug. 26 in Las Vegas, a well-placed source told Yahoo Sports on Wednesday.

Mayweather and McGregor both confirmed the fight on social media on Wednesday.

According to UFC president Dana White, the fight will be at T-Mobile Arena in Las Vegas and will be contested at 154 pounds. It will be a standard, 12-round boxing match with 10-ounce gloves. The Nevada Athletic Commission on Wednesday approved the request from Mayweather Promotions to put on a boxing card on Aug. 26 at the MGM Grand. The venue could change, however, to T-Mobile.

The bout will be distributed via Showtime pay-per-view. It will be an entirely boxing card. Mayweather Promotions will be the lead promoter.

It is a stunning development given that Mayweather, the greatest boxer of his era, had said he was retired after compiling a 49-0 pro record from 1996 through 2015. But with a fight which could pay each man in excess of $100 million, he reconsidered.

Mayweather is considered the greatest boxer of his generation and among the best of all-time. The fight with McGregor, in addition to paying him in excess of nine figures, will give him the opportunity to improve to 50-0.

Floyd Mayweather (L) and Conor McGregor will meet in the ring on August 26. (Getty) More

McGregor is one of the elite mixed martial arts fighters in the world, but has never boxed before, either amateur or pro. He won the UFC’s featherweight title in a 13-second knockout of Jose Aldo on Dec. 12, 2015. He then split a pair of non-title welterweight fights with Nate Diaz before knocking out Eddie Alvarez on Nov. 12, 2016, in New York to win the lightweight belt and become the first fighter to hold two UFC championships simultaneously.

Jeff Sherman, the oddsmaker at the Westgate sports book in Las Vegas, made Mayweather a minus-1000 favorite. McGregor is plus-650.

The bout came together organically, as McGregor first spoke about his desire to fight Mayweather and then they began going back-and-forth on social media.

On March 15, White appeared on Conan O’Brien’s television show and said that because of the large amount of money involved, it was possible the deal was done.

In an interview with Yahoo Sports the next day, he expanded on his thoughts.

Is this thing possible? Yeah, I think it’s possible. Do I think it can happen? I do, because there’s so much involved. But it’s a long, long way away from happening. We’re no closer today than we were when we were talking two months ago.

White had been in talks with Mayweather adviser Al Haymon since the beginning of the year. While the bout always seemed like a long shot because of McGregor’s lack of boxing experience, once the two principal negotiators got together, that made it far more real.

White announced on May 18 that he’d reached a deal with McGregor. At that point, the issue was coming to terms on a financial split with Mayweather.

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