Critics have been almost universal in their stance that UFC lightweight champion Conor McGregor has almost no shot of defeating former pound-for-pound king Floyd Mayweather in their Aug. 26 boxing match in Las Vegas. 

That doesn't mean bets haven't stopped coming in to sports books from those hoping for a massive upset. 

In fact, because of the amount of money coming in for McGregor (21-3 in MMA) ahead of his pro boxing debut, the 40-year-old Mayweather (49-0, 26 KOs) continues to become less of a betting favorite by the day. 

As of Wednesday, the latest odds from Bovada saw Mayweather, who returns from a two-year retirement to face McGregor at T-Mobile Arena in Las Vegas (Showtime PPV, 9 p.m. ET), as just a -450 favorite. McGregor, 29, is listed as a +325 underdog. 

When you consider that Mayweather originally opened as high as a -2250 favorite before the fight was official in November (with McGregor at +950), the constant change in odds has been staggering. On the day the fight was announced in June, Mayweather's odds went down to -800, with McGregor coming back at +500. 

According to, betting Mayweather to win at the current odds provides a better value than every Mayweather fight (with the exception of the Manny Pacquiao and Canelo Alvarez fights) dating back to 2011. 

To better illustrate that point, McGregor is now less of a betting underdog than Mayweather opponents Marcos Maidana (both fights), Miguel Cotto, Zab Judah, Andre Berto and Victor Ortiz.