Floyd Mayweather ended his perfect pro career having won every fight that mattered, though there remains an audience convinced he will fall in one that won’t count.

The majority of betting action has been placed on longshot underdog Logan Paul to conquer the Hall of Fame former five-division champion in their high-profile exhibition. Mayweather (50-0, 27KOs) remains the odds-on favorite to prevail although punters like the chances of Paul (0-1) to pull off the upset this Sunday, live on Showtime Pay-Per-View from Hard Rock Stadium in Miami Gardens, Florida.

Data compiled by Oddschecker.com notes that 57.6% of the betting action has come in on Paul over the past week. Supporters of the YouTube star and boxing novice have driven down odds from as high as +2500 when the fight was first rumored to roughly +400 on the eve of their scheduled eight-round exhibition contest.

That level of confidence comes despite the fact that Paul lost his lone sanctioned pro bout and that the only manner in which either boxer can win is by knockout. Paul’s pro debut came in Nov. 2019, dropping a disputed six-round split decision to fellow YouTube personality KSI in a rematch to their Aug. 2018 exhibition bout which ended in a draw.

Mayweather was first floated as -10000 (100-to-1) favorite when the matchup was rumored in 2020, with the sport’s best fighter of his generation now hovering above -700. Less than 38% of bets collected have been placed on Mayweather, the 44-year-old retired boxer who is now a full-time promoter and forever a full-time entertainer.

“The odds are dictated by the market, and the bets have been on Paul,” Oddschecker.com spokesperson Kyle Newman told BoxingScene.com. “It’s tough to see any way he wins this fight, especially since he couldn’t even beat a YouTuber, but bettors are doing their thing. Perhaps the odds-on Paul were simply too good to pass up, but even so it’s hard to see him actually winning the fight.” 

Mayweather implied chances of winning on Sunday are 81.4% according to current odds, down from 90% earlier in the week. Paul’s implied chances of winning according to bettors have increased from 16.7% to 18.6% over that same period.

Sunday’s bout will mark Mayweather’s first ring appearance since an exhibition on New Year’s Eve 2018 in Japan, when he traveled to Japan to face local hero and celebrated kickboxing champion Tenshin Nakasuwa. The non-sanctioned bout was fought strictly under boxing rules, with Mayweather claiming a 1st round victory.

Similarly, the exhibition between Mayweather and Paul will not be sanctioned by the Florida State Boxing Commission (FSBC).

The disparity in experience and skill level were contributing factors, in addition to the two fighting three weight divisions apart. Mayweather weighed a career-heaviest 155 pounds for Sunday’s exhibition, though still nearly 35 pounds lighter than Paul who weighed 189 ½ pounds. Mayweather’s contractual limit was 160 pounds, while Paul—who weighed 199 ¼ pounds for his aforementioned loss to KSI—could not weigh more than 190 pounds.

With the fight not sanctioned by the FSBC, betting action is not legally allowed in the United States. The above stated figures are for gambling activity generated from overseas.

Jake Donovan is a senior writer for BoxingScene.com. Twitter: @JakeNDaBox