March Madness betting roundup: Sportsbooks had perhaps best first tourney weekend ever as bettors lose

Frank Schwab
·4-min read

Bettors prefer favorites and overs. It doesn't matter the sport or event, more often than not, that's how casual bettors play games.

In this NCAA men's tournament, probably the biggest betting event in sports, underdogs and unders dominated. You can do the math.

"Tough week for the bettors, very tough," said Jeff Stoneback, the director of trading for MGM Resorts. "Arguably the first three days of the tournament was probably the best three days ever for the books on the first weekend."

Favorites rallied on Monday, but the damage had been done.

Through the first round of the tournament and the First Four, underdogs were 22-13. The under was also 22-13, with first-half unders hitting at an even better clip.

Stoneback said MGM won about half as much on Loyola Chicago's second-round win over Illinois as it won on all the first round combined. Illinois' loss also took care of one of the three teams that BetMGM had liability on in the futures market. The Illini, which was +8000 before the season to win, accounted for 11.8% of the money bet on who would win the NCAA men's tournament before the big dance started.

The story of the first weekend of the tournament was the wild number of upsets across all regions. Gonzaga is the only top-four seed remaining in the West. There are four double-digit seeds in the Sweet 16, including No. 15 Oral Roberts. The South region has a Nos. 2, 8, 11 and 12 left. It's chaos.

The unpredictability made for a fun first weekend. Just not for bettors.

Evan Mobley of the USC Trojans dunks as Ochai Agbaji of the Kansas Jayhawks defends in a second-round NCAA tournament game. (Photo by C. Morgan Engel/NCAA Photos via Getty Images)
Evan Mobley of the USC Trojans dunks as Ochai Agbaji of the Kansas Jayhawks defends in a second-round NCAA men's tournament game. (Photo by C. Morgan Engel/NCAA Photos via Getty Images)

Favorites finally have a big day

After days of underdogs, the favorites covered almost every game on Monday.

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That included USC, a lower seed that was favored over Kansas and mauled the Jayhawks. Oregon won outright as an underdog against Iowa to start the day, then favorites swept the board.

For the first weekend, the final tally was underdogs ruled with a 29-22 against-the-spread record, even with the rough day on Monday. The under went 27-21-1.

Gonzaga's big line, again

The sportsbooks aren't able to keep up with Gonzaga. In the first round the Bulldogs were the first 30-point favorite in the NCAA men's tournament since 2015, and they covered. They were the biggest favorite in the second round, rising all the way to -15.5, and covered. And in the Sweet 16, they're the biggest favorite in many years.

Gonzaga is a 13.5-point favorite over Creighton. That's the biggest Sweet 16 spread since at least 2014, according to Matt Eisenberg's tournament guide. There have been only three double-digit spreads in Sweet 16 games in that time, the largest being Kentucky as a 13-point favorite over West Virginia in 2015. The underdogs went 2-1 in those games, though Kentucky beat West Virginia 78-39 in 2015.

Given that Gonzaga will face No. 5 seed Creighton in the Sweet 16 and either a 6 or 7 seed in the Elite 8, the spreads on the Bulldogs will keep being high.

Monday's worst beat

There weren't many games that came down to the end on Monday in regards to the spread, but Oklahoma +15.5 bettors (were there any? Or was everyone on Gonzaga?) had to feel sick.

Oklahoma played well in the second half and looked like it was on its way to covering until Gonzaga guard Jalen Suggs had a breakaway and Oklahoma's Elijah Harkless got a flagrant foul. Many didn't see this as a flagrant foul:

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Whether or not it should have been a flagrant, it was called and that led to Gonzaga getting three free throws to take a 17-point lead. Oklahoma had a chance to cut the deficit to 15 and get ahead of the spread, but missed a free throw after that and never got the ball back. Gonzaga had a pretty fortunate half-point cover.

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