Las Vegas facing 'one of the worst losses in history' as odds on Conor McGregor beating Floyd Mayweather shorten

The odds on McGregor to beat Mayweather have been steadily getting shorter, as money continues to flood in on the Irishman emerging victorious against the odds on Saturday night

Las Vegas sportsbooks have been warned that they face “one of the worst losses in history” if Conor McGregor unexpectedly triumphs over Floyd Mayweather on Saturday, as punters continue to back the Irishman at rapidly shortening odds.

Mayweather is widely expected to win the super-welterweight contest, given that he boasts a flawless professional record of 49-0 while McGregor is a boxing novice.

Initially, the odds reflected this gulf in experience, with the Westgate Las Vegas Superbook first posting Mayweather as a -2500 favourite (with McGregor a huge +1100 underdog) in a hypothetical bout back before the official announcement.

But since then the sportsbooks have been spooked by the large sums of money being wagered on a McGregor victory, with approximately 16 of 17 tickets placed on the Irishman to triumph, all with hefty payouts. This has driven the consensus price on a Mayweather victory to -475, with McGregor’s odds shortening to +375.

“This is like hanging -3 on the Super Bowl and seeing the line move to -8,” Jay Rood, vice president of MGM Resorts race and sports, told ESPN, before adding ominously: “This could be the worst loss in the history of MGM Resorts.”

“All I know is we're less than a week away from making a lot of money or getting [clobbered]," Nick Bogdanovich, director of trading at William Hill, added.

“I never dreamed in a million years that it would create this kind of frenzy.”

Bookmakers in the UK also stand to make a considerable loss if McGregor stuns Mayweather in the ring on Saturday night, with Oddschecker revealing that the American’s odds hit a new high this week.

For the first time since the fight’s official announcement, Mayweather has hit odds of 3/10, which is a long way from the 1/25 he was initially priced up at back in May.

In contrast, McGregor — who was initially instated as a 7/1 underdog — is now as short as 13/5 with one British bookies.

The odds on McGregor winning just keep shortening (Getty) (Getty Images)

“With just a few days left before the fight, early reports suggest that punters are going big on the underdog,” James McGurn, Vice President Digital Content & Gambling at Worldpay, told The Independent.

“Britain’s bookmakers could be nursing heavy losses if McGregor pulls off a huge upset against the undefeated Mayweather. Needless to say, a rush of late wagers for Mayweather on fight night is predicted and could help to provide some balance for the bookies.

“Our data from Haye vs. Bellew earlier this year suggests that online gambling transactions increase by over 250% during major boxing events. And with unprecedented hype in the build-up to the Mayweather vs. McGregor “megafight”, we are predicting an ever bigger surge this weekend.”

The bookmakers will be cheering on Mayweather this weekend(Getty) (Getty Images)

The interest in the Mayweather vs McGregor bout — and the growing belief that the Irishman may actually stand a chance against the American legend — has also affected the odds on who the UFC champion will fight next.

Betsafe have instated Mayweather as his most likely next opponent, with an immediate rematch priced at 2/1.

A return to the UFC seems his most likely course of action — with Khabib Nurmagomedov and Nate Diaz at 4/1, and the winner of Tony Ferguson vs Kevin Lee available for 6/1 — while a boxing match to settle his feud with Paulie Malignaggi is at 16/1.

The winner of Gennady Golovkin vs Saul Alvarez is meanwhile available at 25/1.