How Public Betting Trends Move NFL Lines and Odds

Late into a subfreezing night at Arrowhead Stadium — and after 60 minutes of play in the 2019 AFC Championship — Tom Brady led the Patriots on a 13-play, 75-yard drive capped off by Rex Burkhead's 2-yard touchdown run, giving the team a 37-31 OT victory against the Chiefs and earning them a trip to the Super Bowl.

And the moment Burkhead crossed the goal line, oddsmakers from around the world wasted no time posting the betting lines and odds for the Super Bowl LIII matchup. The Rams — who had won earlier against the Saints in the NFC Championship — opened as a consensus 1-point favorite at online sportsbooks.

However, before the clock struck midnight, the point spread had swung the other way and now listed the Patriots as 2-point favorites to win the NFL title.

By the time the sun came up the following morning, oddsmakers had moved the line even further in favor of the Patriots. Every notable football sports betting site now had Brady’s bunch listed as either 2.5-point or 3-point favorites before Super Bowl Sunday arrived.

But how and why did this happen?

Money On Both Sides

When NFL oddsmakers post a betting line — whether it be a point spread, money line, totals, prop bet, futures, etc. — the “public,” or everyone eligible to bet on the line, begin to place money on the side of the line that they believe will pay out.

Their job is to not only set the initial betting lines but also move them afterward based on how the public is wagering.

Since vigorish or “juice” — a small tax for letting you place a bet with a sportsbook — is found on every set of odds and is how any sportsbook makes a profit, in a perfect world, oddsmaker would love to see both sides of a betting line receive an equal amount of action from the public. Then they could pack it up and leave since their job would be done for that week’s slate of NFL games.

However, the public rarely — if ever — is 50/50 on any given line because one team is typically perceived as the favorite and the other as the underdog before kickoff, oddsmakers need to call an audible.

Shifting The Odds In Their Favor

Let’s use the previously mentioned Super Bowl LIII for our example, where the oddsmakers opened the Rams as a 1-point favorite against the Patriots.

After the line came out, oddsmakers were forced to push the spread to the Patriots favor since most of the public money coming in was on Brady and Belichick, who was attempting to win a sixth Super Bowl title since the turn of the century.

If they hadn’t changed the opening point spread, then more and more money would likely have continued to come in on the Patriots. Again, USA sportsbooks don’t want a lopsided amount of action since it means they will lose money if the public is right.

Oddsmakers Can Be Wrong

On January 24, just four days after the opening point spread was posted, Las Vegas sportsbooks reported to Business Insider that 80% of all the bets they had accepted were on the Patriots, who were attempting to win a sixth Super Bowl title for Belichick and Brady.

We can see that when 80% of the public bet money on the Patriots, it caused a swing of 3.5 or 4 points depending on the sportsbook since the opening underdogs entered the game as a near consensus 2.5-point favorite.

From an oddsmakers’ perceptive, having 80% of the public money on the Patriots wasn’t such a bad thing since their computer algorithms predicted that the Rams were going to win by 1 or more points on a neutral field.

Everyone Is Right In Hindsight

To be fair to the oddsmakers, the Rams had a much more impressive resume coming into Super Bowl Sunday when looking at only the 2018 season. The team finished with a 13-3 overall record in the regular season and had just beaten the Saints, who were the Super Bowl favorites among the four teams playing in the conference championship round, on the road in the Superdome.

The Patriots on the other hand seemed to limp into the playoffs after having a bit of an up and down season, one where people coincidently forget that they got thrashed by non-playoff teams like the Lions and the Titans, but ultimately finished with an 11-5 overall record.

After beating MVP Patrick Mahomes and the Chiefs in Arrowhead, oddsmakers were obviously a bit wary since by making the Rams a 1-point favorite, they were betting against Belichick and Brady, the greatest head coach and quarterback ever that had won five Super Bowls and was making their 9th appearance in the big game — both are records.

But despite the influx of cash on the Pats, the Rams appeared to be an excellent value to the oddsmakers since their 1-point favorite just needed to cover the 2.5-point spread, and then the sportsbooks would win big. If the Patriots won by 3 or more, then the sportsbooks would lose big.

Even A Blind Gut Wins Once In A While

As we all now know, the Patriots defeated the Rams in Super Bowl LIII by a score of 13-3 in the lowest scoring title game since the AFL-NFL merger and covered the 2.5-point spread set by the oddsmakers.

Anywhere from 75% to 80% of the public won their bets on the two-decade-long dynasty from New England, and NFL sportsbooks around the world lost millions of dollars on the point spread even after shifting the odds. Fading the public wouldn’t have worked in this scenario, and the oddsmakers’ algorithms ended up being wrong even though the value was on the Rams.

But if you ask any of them whether they would access value differently with what they know now, and the answer would likely be a resounding “no” since oddsmakers make a living out of beating the public on a regular basis, and one lost battle is hardly the end of the NFL betting war.

That’s the thing about value: it’s how you perceive it. After all, one person’s trash is another person’s treasure. After watching Brady and Belichick win five Super Bowls in eight attempts, the public saw value on the Patriots with the Rams as a 1-point favorite and bet against the algorithm’s perceived value.

In the end, there is not any one factor that can lead to movement with NFL betting lines and odds since anything remotely related to the game of football can affect how the oddsmakers and the public perceive a particular matchup, and in turn, swing the spread one way or the other.

Share