A wild pack of underdogs took a bite out of the betting public's wallet in Week 1 of the NFL season.

Legal sportsbooks and betting apps in the US saw their bottom lines bulge after nearly a dozen heavily-backed favorites fell against the spread on Sunday.

With millions of new NFL betting fans wagering on pro football legally for the first time this season, the sportsbooks should be capitalizing on marquee upsets all year.

“We had extremely good results today. I couldn’t have asked for a better start to the season. Almost all of the big decisions in the early games went our way and we picked up some more in the late games,” said Thomas Gable of the Borgata in Atlantic City.

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The same overall success for the sportsbooks held nationwide.

“Overall, a strong start to the NFL season for the book,” PointsBet said.

Underdogs went 11-3 ATS on the day. The underdog Cowboys also covered their 8-point line against the Bucs in Thursday night’s season opener. That left the underdogs 12-3 ATS heading into Monday night's game between the Ravens and host Raiders.

The most remarkable underdog cover of the day came in Detroit. At one point, the Lions trailed the 49ers 38-10 before losing 41-33. The Lions even had the ball inside 49ers territory when the game ended. The NFL line opened with Detroit as +7.5-point underdogs before swelling to +9 at the close.

“The success of underdogs across the board led to several favorable results for PointsBet Sportsbook, with the public heavily betting on favorites in nearly all games,” the operator said.

The number of bets and total handle were a record at PointsBet for an NFL Sunday. Volume was up 4% over last year, even while factoring in the number of new betting jurisdictions.

Here are the best results for the book at PointsBet:

The public was crushed in all three. The Packers absorbed 80% of the spread handle and 91% of the moneyline cash. The Jaguars were backed by 75% of the spread and 72% of the moneyline handle. Finally, the Bills drew 60% of the spread handle and 82% of all dollars wagered on the moneyline.

At DraftKings Sportsbook , the most-bet team by handle and number of bets was the Chicago Bears (+8), who failed to cover in a 34-14 loss to the host L.A. Rams in their opener at SoFi Stadium.

The sportsbook also enjoyed big wins thanks to upsets by the Cardinals, Bengals and aforementioned Saints. The Bengals (+3) beat the visiting Vikings 27-24 in overtime. In terms of handle, 80% of the cash backed Minnesota on the spread.

With sports betting in Arizona now live, it was a good day for the few who backed the Cardinals on the road in Tennessee. The Cardinals traveled to the Titans and dismembered Tennessee 38-13. In terms of handle, 76% of the bettors at DraftKings backed the Titans (-2.5).

Jameis Winston threw 5 TDs in that 38-3 win over the Packers (-2.5) in Jacksonville. At DraftKings, the public supported Aaron Rodgers & Friends with 76% of the handle at -180 on the moneyline and a dizzying 92% of the spread handle.

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Baptism By Fire For Rookie QBs

Three rookie QBs made their NFL debut as starters on Sunday: Mac Jones for the Patriots, Zach Wilson for the Jets and Trevor Lawrence for the Jaguars.

All three quarterbacks lost and none covered the spread. But they should not feel too bad, Tom Brady, Patrick Mahomes and Rodgers didn’t cover this week, either. Here’s a breakdown:

Lawrence and Wilson went first and second in the draft, while Jones fell into Bill Belichick’s lap at No. 15.

Jones kept the Patriots within range of the Dolphins all day, but was victimized by a pair of lost fumbles by his running backs and eight Patriots penalties for 84 yards. This version of the Saban Bowl was won by Miami second-year QB Tua Tagovailoa and the Dolphins' ferocious defense.

Wilson’s day was a tale of two halves. He hit just 6 of 16 attempts in the first half as the Jets fell behind 16-0. He found Corey Davis for a pair of second-half TDs. He was sacked six times and will need help from the offensive line if he expects to survive a 17-game season intact.

The Jaguars extended their losing streak to 16 as they were hijacked by the Texans. Much of Lawrence’s success came long after the outcome of his opener was certain.

The other two QBs taken in Round 1 also played Sunday. Each produced scores. Trey Lance, taken by the 49ers at No. 3, came in briefly for Jimmy Garoppolo against the Lions in the first quarter and threw a 5-yard TD pass on his one and only pass of the game. Chicago rookie Justin Fields took over for Andy Dalton at times Sunday night and scored a touchdown on his first run from scrimmage.

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Winners & Losers

Here are some big bets that occurred on Sunday and how the bettors fared:

Major Wagers

Parlays & Props

At DraftKings, the book broke even in terms of wins and losses on its top 10 most-bet NFL props. Here is a look at each wager and whether the prop covered or not:

Wilson’s second TD and the cover came with just 1:56 to play in the game. Moore was one of seven players who caught passes from Kyler Murray in the Cardinals’ 38-13 demolition of the host Titans. Moore finished with four catches for 68 yards.

Plays Of The Day

$85 → $2,169.49

A nice #SameGameParlay hit to start the NFL season! 🤑

(via @MDogg_) pic.twitter.com/wkdDJIK9Rv

— FanDuel Sportsbook (@FDSportsbook) September 12, 2021

One customer at DraftKings won $16,400 after wagering $4,000 on Rams covering the closing -8.5 line, Matthew Stafford’s longest pass being for a TD, and Stafford going over 273.5 yards passing.

Another DK bettor won $20,000 after betting $500 on Van Jefferson to score the first TD Sunday night at +4000.