- The Arizona Cardinals (5-3-1 against the spread) are 4-point favorites on Sunday (4:05 p.m. ET, CBS) against the Oakland Raiders (2-7 ATS).
- A majority of spread tickets are on the Cardinals, but history tells us bad ATS teams are undervalued against good ATS teams.
In one of the most lopsided games of Week 10, 74% of spread tickets were placed on the Kansas City Chiefs as 16.5-point favorites against the Arizona Cardinals.
The 16.5-point spread was tied for the largest of the 2018-19 NFL season (Vikings -16.5 vs. Bills, Week 3).
Why did recreational gamblers have such faith in Kansas City? After nine weeks, Patrick Mahomes was the MVP favorite and the offense was averaging 36.3 points per game (1st in the NFL).
Plus, the team covered its first seven games and was an NFL-best 8-1 against the spread (ATS).
Unfortunately for Chiefs bettors, Andy Reid’s team won but did not cover.
After a profitable start to the season, bettors are expecting Kansas City to continue cashing tickets, but history tells us a team’s ATS record in the first half of the season is not predictive of future ATS success.
Using the Bet Labs database, I pulled ATS records for every team since 2003 and compared first-half season results to those in the second half. That is sample of 480 teams.
Then I used the correlation coefficient to determine if there was a relationship between how teams perform ATS in the first half and second half of NFL seasons.
A correlation coefficient of 1 indicates perfect correlation, -1 means there is perfect negative correlation and 0 indicates no correlation.
The correlation coefficient is -0.04, which means a team’s first-half ATS results are not predictive of what will happen in the second half of the season.
The most profitable teams, like the Chiefs, tend to regress as the playoffs approach. Squads that won six or more games ATS in the first half had a combined record of 300-79-5 (79.2%) ATS in Games 1-8.
In the second half, those same teams went 190-185-9 (50.7%) ATS.
The same is true for the worst teams at covering the spread. Since 2003, 70 teams won two or fewer games ATS in the first half, going 121-410-29 (22.8%) ATS.
In the second half, these teams experienced positive regression and went 287-256-17 (52.9%) ATS.
Knowing teams regress to the mean over the course of a season creates an opportunity for contrarian gamblers.
Bad ATS teams vs. Good ATS teams
Since 2003, teams that have covered the spread in 30% or less of games have gone 652-578-31 (53%) ATS in the following game.
These teams become even more profitable when they face an opponent that has consistently won for bettors (60% win rate ATS):
In Week 11, the Oakland Raiders (2-7 ATS) travel to Arizona to play the Cardinals (5-3-1 ATS). In early betting (see live odds), 69% of spread tickets are backing the Cardinals as 4-point home favorites.
The public is fading Oakland. Contrarian bettors can find value by backing the Raiders.