With the superfight between undefeated boxer Floyd Mayweather Jr. and UFC champion Conor McGregor being made official Wednesday, bettors are already putting their money where their mouth is.
Facing an opponent who has never boxed professionally before, Mayweather is a heavy favorite. But in the days since the announcement, Las Vegas sportsbook odds have seen the 41-year-old superstar’s advantage go from -1,100 (meaning a $1,100 bet on Mayweather would yield $100) to -600, ESPN reported Saturday.
What’s responsible for the sudden shift?
ESPN reported that Vegas sportsbooks have seen a “flurry of betting action” in which most of the bets are on McGregor, but most of the money is on Mayweather. Reportedly, 140 of the first 144 bets at Caesars Palace sportsbooks were placed on McGregor.
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Contributing for Forbes, Tim Wood wrote that somebody likely placed a huge bet on McGregor that played a big role in moving the line.
“Does that mean that insiders really believe McGregor can win? Highly unlikely,” Wood wrote. “The more logical explanation is that one or many of the sharks are manipulating the line in preparation to make a huge bet on Mayweather when they get what they believe will be the most favorable odds.”
The fight, planned for Aug. 26, has been major talking point in the sports world since rumors and speculation started to circulate in 2015.
In another ESPN article, Mackenzie Kraemer compared McGregor’s underdog line of +700 (earlier this week) to similar underdog lines from the past few years. In advance of Holly Holm’s victory over then-undefeated Ronda Rousey at UFC 193, Holm was a +800 underdog.