By Mark Lamport-Stokes
LAS VEGAS (Reuters) - Gamblers have flocked in huge numbers to Sin City for Saturday's welterweight showdown between Floyd Mayweather Jr. and Manny Pacquiao which experts believe will be one of Nevada's most heavily bet-upon sporting events.
The National Football League's showpiece Super Bowl accounts for the top 20 events of all time for sports betting in the "Silver State" but industry insider Jay Kornegay predicts that the Mayweather-Pacquiao bout could break that trend.
"The biggest sporting events for betting have always been the Super Bowl, based on handle," Kornegay, vice president of race and sports operations at the Westgate Las Vegas Superbook, told Reuters.
"But this fight has a chance to break that trend and possibly even be in the top 10 events of all time.
"This is the biggest fight I have ever been a part of, and I've been in this industry for almost 30 years. The amount of betting attention this fight has seen prior to the fight weekend is unprecedented."
Jay Rood, vice president of race and sports book at MGM Resorts, expects the Mayweather-Pacquiao wager total to be between $60 and $80 million.
"It's really going to be concentrated on the Las Vegas Strip corridor, the further you get away from the Strip, the less financial impact the fight is going to have to the sports books around the state," Rood told Reuters.
"But there are plenty of people coming to town with some rather large bank rolls so I think it's going to be solidly north of $60 million."
Neither Kornegay nor Rood expect the fight to eclipse the record $119 million bet in Nevada for the 2014 Super Bowl between the Seattle Seahawks and Denver Broncos, but they agree that Saturday's bout could come close.
"Most of the Super Bowls have exceeded at least $80 million, dating back probably to 1995, but this fight has got the potential to crack that 20-year reign," said Rood.
The early wagers favor Pacquiao, who is a 2-1 underdog, while the big spenders tip Mayweather.
"I would say 87 percent of the tickets have been on Pacquiao with almost all of the larger wagers, meaning five figures and above, on Mayweather," said Kornegay. "We expect those betting patterns to continue."
MGM Resorts has Mayweather listed as a minus-200 favorite, so a $200 bet would win $100, while Pacquiao is a plus-170 underdog, meaning that a bet of $100 would win $170.
The biggest bet taken so far by MGM Resorts has been $500,000 on Manny Pacquiao, but Rood expects that to be surpassed over the next 24 hours.
"You normally take those large wagers on Friday or Saturday of the fight, and I'm hopeful that we are going to get some seven-figure wagers," Rood said.
"We have had some inquiry on placing a seven-figure wager on Mayweather, actually several of them, but usually you get about 25 percent of the inquires actually show up at the counter and place the cash."
The fight has also led to a few unusual proposition bets being created.
"Most of Mayweather's recent fights have ended in a decision so we said if it's going to go to a decision most likely, let's have a prop bet on that," Rood explained. "So we have a judges' scorecard over-under.
"We put the judges' accumulative score and you bet whether you think it's going to be over or under a certain point. And we established Mayweather's point to be 347.5 and Pacquiao to be 336.5."
There are also 'pick the knockout round' bets.
"We have the five packets," said Rood. "Floyd by a knockout or decision, Manny by a knockout or decision and then the draw."
(Editing by Gene Cherry)