Floyd Mayweather vs Conor McGregor: when is the fight, where will it be held and what are the odds?

Floyd Mayweather Jr. will come out of retirement to meet UFC star Conor McGregor in a much-anticipated boxing match that will feature two of the top-selling fighters in the world.

The two fighters both announced the fight after months of speculation about whether Mayweather would be lured back to the ring at the age of 40 to face a mixed martial arts fighter who has never had a pro boxing fight.

Here's everything you need to know about the fight.

When will it take place?

The event will take place on Saturday, August 26. While the times haven't been announced, it will certainly be a late night or very early start for viewers in the UK. 

Where will it be held?

The bout will take place at the T-Mobile arena on the Las Vegas Strip in Nevada. The venue has held major fights in the past, including UFC 202, in which McGregor beat Nate Diaz on points. 

How can I watch it?

Details are still to be confirmed but the fight will be a pay-per-view event, organised by Showtime Sports. 

The price has not been decided, though it is expected to be at or near the $99.95 charged for Mayweather's 2015 fight with Manny Pacquiao that drew a record 4.4 million pay-per-view buys.

"This is really an unprecedented event," said Stephen Espinoza, who heads Showtime Sports. "Really we haven't seen anything in modern history that resembles it, it's impossible to predict how many sales this will do."

What are their records?

Mayweather retired in 2015 with an unblemished 49-0 professional boxing record.

He is widely regarded as one of the best defensive fighters ever, and prides himself on his ability to evade punishment with his skillful movement about the ring while making adjustments against opponents on the fly.

A win for Mayweather would move him ahead of former heavyweight great Rocky Marciano, who also retired with a perfect 49-0 career record. 

McGregor, the UFC's reigning lightweight champion and former featherweight champion, is known as much for his bravado as for his explosive knockout power inside an MMA octagon.

The 28-year-old Irishman became the first UFC fighter to hold two belts simultaneously when he knocked out Eddie Alvarez in New York last November for the lightweight championship.

The UFC stripped McGregor of his featherweight belt shortly after that fight when he announced he would be taking some time off after he and long-time partner Dee Devlin had their first baby in May.

Known for his devastating striking and highlight-reel knockouts, McGregor is also quick and irrational on his feet, but few would back him to beat one of the most complete boxers of all time.

What are the rules?

The fight will be held under boxing rules, presenting a huge challenge for mixed martial artists McGregor as he faces off against one of the greatest defensive boxers in history.

Adding to McGregor's challenge, the fighters will be using 10-ounce boxing gloves instead of the smaller UFC gloves and he will not be allowed to use the leg kicks or takedowns that are used in mixed martial arts.

McGregor will weigh in at 154 pounds, UFC president Dana White told ESPN.

What are the odds?

Oddsmakers immediately predicted a Mayweather win. William Hill put the veteran fighter at 11-1 favourite.

Oddsmaker Nick Bogdanovich said the odds would be even more lopsided if it wasn't for the deluge of small bets expected to come in from UFC fans on their fighter.

"Realistically if we were just putting up a number and didn't have to take bets on it, Floyd would be 100-1," Bogdanovich said. "But this will be a very, very big betting fight for sure, one of the biggest ever."

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What have they said?

Floyd Mayweather Jr

The boxing great said in May that "it's the only fightthat makes sense (for me). When Floyd Mayweather fights, it's history".

"The only thing I am chasing is my own records. And I mean pay-per-view records. We have to give the people what they want to see. The fans demand that fight; we have to give them what they want to see to make them happy."

In an interview with the Telegraph in  March, Mayweather said: "The difference between me and him is this: He has to fight. If I was him and I was smart, before I lose again in the UFC I'd let Floyd Mayweather kick my a** for a lot of money. It makes business sense.

"This guy said I'm a p***y, I'm scared, I'm a chicken. All 49 said the same thing and all the results were the same.

"When I was a young fighter I could brag and boast and say I'm going to take his a** and do this and that. I'm Floyd Mayweather. But once I reached the top I didn't have anything to say."

Conor McGregor

The Irishman stole the headlinesafter his compatriot Michael Conlan's winning debut as a professional boxer in March. 

"Watch me take over boxing, trust me on that," McGregor told the media. "Watch me step in and shock the whole damn world. I'm 28, a confident m----r f----r, long, rangy, dangerous with both hands. Believe me, I'm going to step in there and knock out Floyd (Mayweather) and you're all going to eat your words. I am boxing."

In an interview with GQ this year, he said: "He's 40 years of age. He's a little…he's got a little head on him. Honestly, my fist is bigger than his head. I sleep people. I put people unconscious. I'm stating facts. If I hit that man, his head is gonna go into the bleachers. You understand that? If I crack that little head of his, it's gonna go clean off his shoulders and up into the bleachers.

Shortly after the fight was announced, White told ESPN: "I talked to Conor McGregor this morning. He is absolutely, 100 percent positive that he wins this fight."

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