Betting public wins big as favorites go 20-1 across 3 major U.S. sports

The house always wins eventually, but the public does occasionally land solid blows to deliver a setback and strike fear into bookmakers.

Monday was a historically profitable day for the betting public, as favorites cashed in 20 of 21 games across the three major U.S. team sports. All four NBA favorites covered the point spread, all four NHL favorites won their playoff games -- and the only underdog to pull off an upset in Monday's 13 Major League Baseball games was the Cardinals against the Cubs.

"We had to go to the [main] cage about three times to get a fill [of cash to restock drawers in order to pay customers]," South Point oddsmaker Jimmy Vaccaro, who's been working behind the counter in Las Vegas for nearly four decades, told ESPN. "The 20-1 mark is something. I can't remember something that bad."

In fact, DraftKings reported that Monday represented its third-largest day of payouts. And the superlatives continued at other operators.

"Worst day of the year [since reopening] by far," executive vice president of the Westgate SuperBook Jay Kornegay told ESPN.

The baseball chalk's 12-1 mark came on the heels of a 12-2 performance by MLB favorites on Sunday, making that .889 win percentage (24-3) the highest over a two-day span in nearly three years.

"The reason yesterday was so bad is the players were playing higher because the weekend was all public winners as well," William Hill director of trading Nick Bogdanovich told ESPN. "Nice roll for the recreational player right now. They deserve it. That's why sports betting is the best bang for your buck. Books only hold 5 or 6%, not 20%."

Bogdanovich also shared that Monday's net loss approached $1 million for Nevada alone, and easily surpassed that mark over its 154 properties across 12 states.

There is only so much a sportsbook can do. The public typically bets favorites and thus the house needs to avoid these types of stretches from repeating.

"We're opening these favorites so much higher than they should be, but the guy who wants to bet the parlays doesn't care what the price is or know the difference," Vaccaro said.

Bookmakers definitely caught some bad breaks all day, and the drama peaked in the final minute of an NBA playoff quadruple-header. The Clippers (-6.5) led the Mavericks by six points when Kawhi Leonard grabbed a rebound with 15 seconds remaining and seemingly was set to dribble out the clock.

But a couple Mavs players applied pressure near halfcourt, which led to a foul and Leonard sinking both free throws, pushing the margin to eight points. Dallas surprisingly called a timeout to advance the ball and give bookmakers slim hope, but Tim Hardaway Jr. missed a 3-pointer in the final seconds.

"I personally have been around too long and seen too many endings for that to affect my mood," oddsmaking veteran and DraftKings director of sportsbook operations Johnny Avello told ESPN. "Unequivocally exceptional business, but ouch."

Monday's NBA playoff slate started with the Nuggets (-4.5) needing overtime to cover against the Jazz, after Utah led by four points with 2:11 left in regulation.

The Celtics (-6) also eked out a fortunate cover in a 109-101 victory over the 76ers. In the final 59 seconds, Boston extended its three-point lead by making all six free throws, while Philadelphia missed both shot attempts, made just one of two free throws and committed a turnover.