Odds on a Conor McGregor knockout victory slashed with just three days to go until Floyd Mayweather fight

The Irishman may be a boxing novice up against an undefeated legend of the sport, but the odds on him winning in emphatic fashion continue to tumble

Irish support for Conor McGregor in his super-welterweight fight against Floyd Mayweather on Saturday night has seen the odds of an early knockout slashed, as UFC fans rush to put money on their man pulling off one of the biggest sporting upsets in history.

McGregor has never boxed professionally before while Mayweather is regarded as one of the greatest boxers of all-time, with a flawless professional record of 49-0. But over the past week, the odds on a McGregor victory have shortened dramatically as punters continue to back an upset.

And in McGregor’s native Ireland, the odds on him knocking out Mayweather at the very start of the fight have more than halved this week.

A McGregor knockout victory in Rounds 1-5 has been cut from 33/1 to 16/1, with the odds on a victory by any method continuing to tumble.

“The betting on this bout has yet to reach its climax but it’s already one of the most punted on events of the year so far,” Betway’s Alan Alger told World Boxing News.

“And as expected, the Irish continue to back their man McGregor ahead of Saturday’s showdown, and the underdog has also been well-punted in most other areas outside of the UK. McGregor has been well-backed in the last few days to win in the early rounds and we’ve cut each of the first five rounds from 33/1 to 16/1.

“Despite strong support from Ireland, the vast majority of the UK aren’t so keen on McGregor. Brits are siding with Mayweather and we’ve taken plenty of five figure bets for Money to oblige at 2/7.”

Earlier in the week, Las Vegas sportsbooks were warned that they face “one of the worst losses in history” if McGregor — a complete boxing novice — unexpectedly triumphs over Mayweather on Saturday.

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.”