Nevada sportsbooks have lost money on only two Super Bowls in the 34 years since the state’s Gaming Control Board started tracking betting on the game in 1991.

But the books suffered their worst Super Bowl loss ever in 1979, when Steelers and Cowboys bettors beat them out of an estimated $3 million — which equates to almost $13 million today — on a day dubbed “Black Sunday” by Las Vegas bookmakers.

Pittsburgh opened as a 2½-point favorite over Dallas, and the line closed at 4½. It landed on 4 in the Steelers’ 35-31 victory over the Cowboys, and virtually every bettor who had action on it won as books got middled — or lost on both sides of the game.

“That game was the biggest losing Sunday for the Super Bowl that ever was,” South Point oddsmaker Jimmy Vaccaro, 78, recounted to the Review-Journal in 2017. “That was the first big loss I took as a young aspiring bookmaker with black hair who could stay out late at night. Those days are gone.”

Frank “Lefty” Rosenthal, the inspiration for Robert De Niro’s character in the movie “Casino,” ran a promotion at the Stardust offering bettors the chance to lay 3½ points with the Steelers and take 4½ points with the Cowboys. When it was over, the line of bettors cashing tickets reportedly stretched from the Stardust to down the Strip.

Longtime Las Vegas sportsbook director Vinny Magliulo was one of the bettors who cashed in on the promotion.

“I was a break-in dice dealer at the Royal Inn at that time. I laid the 3½ and took the 4½ for everything I could at the time, which was a grand total of about 300 bucks,” he said, laughing. “I was on the public side of Black Sunday but converted shortly thereafter.”

After Dallas tight end Jackie Smith dropped a sure touchdown catch in the end zone in the third quarter, Pittsburgh scored two TDs in 19 seconds in the fourth to go ahead 35-17.

But Cowboys quarterback Roger Staubach threw two TD passes in the final 2:27 for the backdoor middle. After his 7-yard strike to Billy Joe DuPree cut the deficit to 35-24, Dallas recovered an onside kick. Staubach then hit Butch Johnson for a 4-yard TD with 22 seconds left, and bettors everywhere rejoiced.

At the time, Vaccaro ran the sportsbook at the Royal Inn, the first casino owned by South Point owner Michael Gaughan.

“At the little Royal Inn casino, where we had just three betting windows at the time, we lost $185,000,” Vaccaro said. “Lefty Rosenthal lost $1.6 million at the Stardust because they were getting all the big action. Jimmy Girard’s place, the Royal Las Vegas, lost about $700,000, and the Union Plaza downtown didn’t do well, either.”

Vaccaro spent half the night paying out.

“In those days, it was handwritten tickets,” he said. “It took me like four hours to grade all the tickets.”

As he was marking a pile of winners, his boss called for a damage report.

“Michael Gaughan calls me from his yacht. He was on the Sea of Cortez or somewhere,” Vaccaro said. “I said, ‘Do you want the good news or the bad news?’ He said, ‘Give me the bad news.’ So I said, ‘The bad news is we lost $185,000.’ He said, ‘What’s the good news?’ I said, ‘The good news is we only lost $185,000.

“Somehow he kept me on, so it all worked out pretty well.”

Here are the two other Super Bowls when bettors beat the books:

1995 Super Bowl: 49ers 49, Chargers 26

In the books’ first Super Bowl loss tracked by the state, bettors won $396,674 when San Francisco crushed San Diego 49-26 as 19-point favorites to cover the largest point spread in Super Bowl history. The game also soared over the total of 53½, as countless bettors cashed Niners-and-over parlays.

But not before the Chargers made bettors sweat a bit in the final minutes. After they scored a touchdown and 2-point conversion to make it 49-26 with 2:25 left, Stan Humphries drove San Diego to the 49ers’ 35-yard line in the final seconds. But they didn’t deliver the backdoor cover for the books as Humphries threw three straight incompletions to end the game.

2008 Super Bowl: Giants 17, Patriots 14

Bettors beat the books out of an official state record $2.57 million when the Giants stunned the Patriots as 12-point underdogs to end New England’s bid for a perfect season.

As is usually the case in the Super Bowl, bettors were all over the underdog on the money line and cashed in when Eli Manning threw a go-ahead 13-yard touchdown pass to a wide-open Plaxico Burress with 35 seconds left.

Vaccaro said the two official losses on the Super Bowl pale in comparison to the 1979 edition.

“What helps in today’s environment, as it didn’t in the ’70s, is we can still make a lot of money off the props, so at least there’s some cushion there, even if you get carried out on the game,” he said. “On Black Sunday, you lived and died with the final score.”

Contact reporter Todd Dewey at [email protected]. Follow @tdewey33 on X.