Super Bowl LVII opening line: How the point spread was built

The matchup for Super Bowl LVII is set, as both the Chiefs and Eagles will go for their second championship in five years. The Chiefs have much of the same coaching staff, quarterback, and core from their last title victory. Meanwhile, the Eagles have few holdovers from Super Bowl LII. They feature a new coaching staff and a younger quarterback than Georgia's recent title-winning signal-caller.

I don't bet Super Bowl futures. Betting a team to win the big game only sets up two weeks of internal debate about a hedge. The ticket holder is likely to make a negative expected-value play in order to lock up some profit, likely around the same amount that they would've won had they just bet conference futures instead.

Having a pre-determined side you're backing for the Super Bowl - decided months ahead of time - is also sub-optimal when trying to handicap the season's last game, especially considering all the prop markets that'll be available. Missing out on a valuable bet in the derivative markets because you're already committed to one side is bad for betting business.

Preseason rating

Before we revise history and suggest that it was fait accompli that the top seeds in each conference would meet in Arizona, it's worth revisiting the perception for both teams before the season started.

Preseason markets

As we discussed in this space before the season, there were concerns about Kansas City's offense after the team traded Tyreek Hill to Miami, and the Chiefs were tied with the Rams for the fourth-highest win total. Meanwhile, the Eagles were bet down throughout the summer to 25-1 to win the Super Bowl before Week 1, but they had the 14th-highest season win total at nine victories, rating them below teams like the Colts and Broncos. They got the upside performance from Jalen Hurts that we hoped for preseason, as well as the hot start that an easy schedule provided.

Midseason rating

By midseason, the Eagles were undefeated and the Chiefs were 6-2. Both were rated equally in betting markets, with only the Bills rated ahead of them as we awaited news on Josh Allen's elbow.

The good teams are always overrated early in the season relative to history, as injuries have yet to pile up and holes haven't been revealed. The Eagles finished the season 3-6 against the spread, and the Chiefs were 2-6-1 ATS after both hit their peak in the market.

Current rating

From when we looked at the conference championship lines one week ago until the close before the AFC championship Sunday, the Chiefs' rating increased as Patrick Mahomes' health seemed to improve. Even with Mahomes making it through a game where he threw for 326 yards and two touchdowns without an interception, the Chiefs aren't getting credit for full health - which my rating assumes - because of how many key contributors left the game against the Bengals.

Meanwhile, the Eagles' rating crept up last week as they hit -3 before the NFC championship. Brock Purdy got hurt on the first drive, so while the Eagles deserve their ticket to Super Bowl LVII, another true test in figuring out a reliable competition-based rating went by the wayside.

With the calculation for home-field advantage removed, the Chiefs should be the slightest of favorites by my ratings. However, their injury issues, and the on-field matchups, need to be evaluated.

Chiefs @ Eagles (-2.5, 49.5)

On Sunday night, as Harrison Butker's kick went through the uprights, sportsbooks started putting up their lines for Super Bowl LVII. A total as high as 51 got the bet down quickly, but the point spread was the most interesting. Circa Sports' Jeffrey Benson tweeted about their opening line:

You'll see an opening line of Chiefs -2.5 was bet across pick'em - a common opener elsewhere - to the Eagles' current position as just shy of a field goal favorite. The cheapest price that this bettor found for the Chiefs at the key number of +3 was -126, but that's long gone.

With almost two weeks until kickoff, and thousands of prop markets yet to be posted, it'll be interesting to see if there's any more important movement in the spread - either up to a flat 3-point spread or back down closer to pick'em.

Matt Russell is a betting writer for theScore. If there's a bad beat to be had, Matt will find it. Find him on Twitter @mrussauthentic.