Good teams win games in the NFL. Unpredictable teams cover spreads in the NFL. Sportsbooks are profitable businesses because they set efficient lines. An efficient line is not one that finishes close to the actual winning margin. An efficient line is one that gets equal money on both sides of the game. As long as equal money is on both sides of an NFL game sportsbook walks away the winner. To see just how good sportsbooks are at setting lines check out each NFL team's records versus the spread. Most teams finish with records somewhere between 7-9 and 9-7 against the spread. Making winning versus the spread a coinflip.
Some teams however are harder to judge than others. Teams who perform better or worse against the spread often fall into two categories, either they are overvalued or undervalued. An example of the former is when a highly ranked preseason team falls well below expectations, yet Vegas continues to make them the favourites. On the other end of the spectrum is the dark horse who defies expectations and continues to win despite the reputation as a lemon. Public perception plays a large role in determining a spread for any game. And sometimes the herd is wrong.
Every season teams can be found that outperform their given spreads. Whether it be sportsbooks giving too much or too little respect to a team. Or the public heavily betting one side. Both scenarios keep lines out of sync with reality. These outliers present smart bettors with opportunity. So, let us look at the three teams who provided the best return in 2020 versus the spread. The spreads used for this article are referenced from Pro Football Reference and are closing game lines for the 2020 season.
Buffalo Bills: 11-5 vs the spread
The Bills went 11-5 against the spread in 2020. The graph shows the spreads Buffalo received throughout the season and how they performed against each spread. Blue indicates the Bills won against a given spread, whereas pink means they lost. The Bills were favoured in 12 games, going 8-4 as the favourite. Buffalo performed well as an underdog in 2020, going 3-1. Their only loss coming at the hands of the Kansas City Chiefs. The average weekly spread for the Bills was -2.2, showing on average Buffalo was a favourite. The weekly deviation was 4.3 points. This deviation is smaller than the other two teams in our conversion. Showing how sportsbooks had a better grasp on how to handicap Buffalo.
Miami Dolphins: 11-5 vs the spread
Miami was favoured in 7 of their 16 games in 2020. Going 4-3 as the favourite. Where the Dolphins shinned was as underdogs. In their 9 games as dogs, they went 7-2 against the spread. The average spread for the Dolphins in 2020 was 0.4. This spread of almost 0 showed how on any given week most people could not tell if Miami deserved to be the favourite or the underdog. The Dolphins also had a weekly deviation of 6.3. This large deviation showed how sportsbooks were unsure of how to handicap the Dolphins. Such large swings in weekly spreads are a sign of how unpredictable the Dolphins were in 2020.
Dallas Cowboys: 5-11 vs the spread. Or 11-5 if you bet against them
Dallas started the 2020 season 0-8 against the spread. A clear sign of underwhelming performance. It took sportsbooks 8 weeks to finally handicap the Cowboys properly. Even before losing starting quarterback Dak Prescott, Dallas was unable to win against the spread. The Cowboys had a weekly average spread of 1.9 in 2020. Showing as time went on it was more likely they received points. Their weekly spread deviation was 6. Like the Dolphins, the spread for Dallas moved heavily from week to week. Dallas was favoured by as much as -7.5 and made underdogs by as much as 14 points. Such a large deviation often presents opportunities to bettors.
A bettor who rode the Bills and Dolphins along with betting against the Cowboys each week would have had a hell of a season gambling. Going 33-15 would have provided a sizeable return. Assuming someone bet 110$ on each game at standard -110 odds they would have walked away with $10,560, having risked $5,280. Doubling your money and finishing with a 68.75% winning percentage is not a bad result for the season. Most people kiss the floor if they hit the breakeven percentage of 52.3%. Meanwhile, a 68.75% winning percentage is more likely to get you thrown out of a casino.
I do not use these teams to show how well Miami and Buffalo played in 2020. I also do not bring them up to laugh at the misfortunes of the Cowboys. I use them as examples. Examples that sportsbooks and the public improperly assess a team’s true performance. Obviously, hindsight is 20/20, but using such an approach throughout the year can help bettors stack some chips in their favour. Gauging whether sportsbooks or the public are out of sync with a team’s true performance is a strategy that can come in handy when evaluating betting options. It is not a full-proof sure-fire way to win money. But trying to decipher what teams the public are too high or too low on can be a profitable way to bet. Talking heads, sports media, and industry experts also help distort perceptions of teams. Seeing through the fuzz can be a competitive advantage for any bettor. Sometimes it pays to go against the grain.