Floyd Mayweather vs. Conor McGregor Opening Odds for Aug. 26 Fight Revealed

First, Floyd Mayweather announced the bout. Now we have the odds for his Aug. 26 return to the boxing ring against Conor McGregor. 

OddsShark posted updated odds that show Mayweather as a -800 favorite (bet $800 to win $100) to win the bout. McGregor is currently a +500 underdog to give Mayweather his first loss as a professional.

Mayweather, 40, has not fought since defeating Andre Berto via unanimous decision in September 2015. Speculation about his return to the ring has been ongoing for more than a year, and the Mayweather camp has focused on a megafight with McGregor for months.

McGregor, UFC's brightest star, came to an agreement with the mixed martial arts promotion about his purse split in May. He has never fought in a boxing ring professionally but is known as perhaps the most powerful pound-for-pound puncher in MMA. The 28-year-old is the only MMA fighter in history to hold two UFC championships concurrently.

For nearly all parties involved, this bout stands to be a major financial windfall.

Mayweather, despite a sordid history of domestic violence and myriad other controversies, remains boxing's most popular name. His May 2015 win over Manny Pacquiao broke every boxing record for pay-per-view revenue, and he should waltz his way to another nine-figure payday against McGregor.

Perhaps the most popular mixed martial artist in history, McGregor is a splendid self-promoter who has combined WWE-style trash talk with unquestioned success. He could make more in one fight against Mayweather than he has his entire UFC career combined.