Super Bowl 2023: Eagles open as betting underdogs vs. Chiefs, line ...

The Philadelphia Eagles weren't Super Bowl underdogs for long.

The Kansas City Chiefs opened as slight favorites in the Super Bowl — 1.5-point favorites at BetMGM. A few minutes after the line was posted, it moved to Eagles -1.5. Then in a couple minutes it moved again, to Eagles -2.5. That's a quick reaction to the Eagles, who looked great in an NFC championship game win.

The over/under for the Super Bowl opened at 49.5 points.

Lines often move for the Super Bowl. There is a lot of money bet on the game, and there are two weeks for bettors to put their money down on either side. The line could continue to change before kickoff on Feb. 12. But the first reaction from bettors was to grab the Eagles.

The Eagles beat the San Francisco 49ers 31-7 in the NFC championship game, easily covering a 2.5-point spread. The Eagles opened at 40-to-1 odds to win the Super Bowl at BetMGM.

In the Eagles' first three trips to the Super Bowl, they were underdogs twice. The Eagles were favored in their first Super Bowl appearance, Super Bowl XV against the Oakland Raiders, and lost 27-10. They were 7-point underdogs against the New England Patriots in Super Bowl XXXIX and lost 24-21, covering the spread. The Eagles won straight up as 4-point underdogs in Super Bowl LII against the Patriots.

The Chiefs won a thrilling AFC championship game 23-20 over the Cincinnati Bengals. The line was anywhere between Chiefs -2.5 and Bengals -2.5 through the week, but the Chiefs covered no matter what the spread was. The Chiefs were just 5-12-1 against the spread before Sunday, one of the worst records against the spread in the NFL this season.

This is the Chiefs' third trip to the Super Bowl in the past four seasons. In the other two Super Bowls with Patrick Mahomes, they were favored. They won as a 1.5-point favorite against the San Francisco 49ers in Super Bowl LIV and lost as a 3-point favorite against the Tampa Bay Buccaneers in Super Bowl LV. Back in Super Bowl IV, the Chiefs beat the Minnesota Vikings as a 12-point underdog. They were a 14-point underdog in Super Bowl I against the Green Bay Packers and lost 35-10.

According to Vegas Insider's Super Bowl point spread history, favorites are 28-25-2 against the spread. One Super Bowl, Super Bowl XLIX, was a pick 'em. That one was won by the Patriots over the Seattle Seahawks.

Last season was an unusual one for Super Bowl bettors. The favorite won but didn't cover. The Los Angeles Rams were a 4.5-point favorite and beat the Cincinnati Bengals 23-20. That was just the seventh time in Super Bowl history in which the underdog covered but didn't win. It hadn't happened since the Pittsburgh Steelers-Arizona Cardinals Super Bowl at the end of the 2008 season.

The last four Super Bowls have all gone under the total. That brings the all-time total to 28 unders and 27 overs (there was no total for Super Bowl I, according to Vegas Insider's history).

If the line moves back toward Kansas City, it could be one of the smallest in Super Bowl history. Before this Super Bowl, there had been only four Super Bowls with a point spread of 1.5 or less. One involved the Chiefs, who were 1.5-point favorites against the 49ers three years ago.