The New England Patriots will begin the two-week buildup to the Super Bowl as the favorites, but not by much.

Heading into Monday, the Patriots were consensus 1.5-point favorites over the Los Angeles Rams in Super Bowl LIII on Feb. 3 in Atlanta.

For about 10 minutes late Sunday night, though, the Patriots were Super Bowl underdogs. That changed quickly.

Some sportsbooks opened the Rams as small favorites, and other bookmakers made the Super Bowl opening line pick 'em.

The early action overwhelmingly was on the Patriots, and the odds quickly moved in New England's favor. By late Monday morning, some books had pushed the point spread to as high as Patriots -2.5.

The SuperBook at Westgate Las Vegas said Sunday night that it was taking five bets on New England for every one bet on the Rams. MGM also reported lopsided early action on the Patriots, including a $100,000 bet on New England -1. It was the largest early wager the book had taken as of late Sunday night.

It's the third straight Super Bowl appearance for the Patriots and their ninth in the past 18 seasons. They advanced with a 37-31 overtime win over the Kansas City Chiefs in the AFC Championship Game. New England is only the third franchise to reach three straight Super Bowls and the first to do so since the Buffalo Bills went to four straight (1990-1993).

The Rams advanced to the franchise's fourth Super Bowl -- second while playing in Los Angeles -- with a 26-23 overtime win over the New Orleans Saints.

"Having L.A. in the big game ain't bad for Vegas bookmakers," said Art Manteris, vice president of race and sports for Station Casinos and a 40-year veteran Las Vegas bookmaker. "Do I worry about one-sided action because of our proximity to L.A.? Not one bit. Just excited about the potential extra handle."

The Patriots kicked off the season as the consensus favorites to win the Super Bowl at sportsbooks. The Rams also were considered among the top tier of Super Bowl contenders and were a popular pick by Las Vegas bettors. In fact, more bets were placed on the Rams to win the Super Bowl than were placed on any other team at the Westgate Las Vegas SuperBook.

The Super Bowl over/under could be found anywhere from 58 to 59, which would make it among the largest ever for a Super Bowl.

A record $158.5 million was bet on last year's Super Bowl between the Patriots and Philadelphia Eagles at Nevada sportsbooks. Since Nevada Gaming Control began tracking the betting action on the Super Bowl in 1991, the state's books have come out ahead of bettors in 26 of 28 years.