Post NBA All-Star Beak Regression: Will Thunder Continue to Cover Against the Spread?
Zach Beeker/NBAE via Getty Images. Pictured: Chris Paul #3 of the Oklahoma City Thunder
- The Oklahoma City Thunder had the best against-the-spread record in the NBA at the All-Star Break
- Using Bet Labs, we analyze how great ATS teams perform in the second half of the season.
The Oklahoma City Thunder have been one of the surprise teams in the NBA this season. After trading away Russell Westbrook and Paul George many expected OKC to tank.
The Thunder started the season 8-12, but are now 33-22 after winning 25 of their past 35 games. Chris Paul is an All-Star, Shai Gilgeous-Alexander looks like a potential star and OKC is currently the sixth seed in the West.
The team’s success hasn’t been limited to the hardwood. At the All-Star break, no team in the NBA has been more profitable against-the-spread (ATS) than Oklahoma City. CP3 & Co. are 36-19 (65.5%) ATS, meaning a $100 bettor would have returned a profit of $1,570 wagering on the Thunder each game this season.
Billy Donovan’s team will host the Denver Nuggets on Friday (8 p.m. ET, ESPN), and the Thunder will be a popular bet given their success at the ticket window. But can the team continue to cover after the All-Star break?
To answer that question, I used the Bet Labs database to pull the pre- and post-All-Star break ATS records for every team the past seven seasons. Then I used the correlation coefficient to determine if there was a relationship between a team’s ATS record before and after the break.
A correlation coefficient of 1 indicates perfect correlation, -1 means there is perfect negative correlation and 0 indicates no correlation.
The correlation coefficient between a team’s pre-All-Star ATS record and its post-All-Star ATS record is -0.0006. This means there is no correlation, and bettors should not expect the Thunder to continue covering the number better than 60% of the time just because Oklahoma City did before the All-Star break.
It is rare for a team to have an ATS win percentage of 60% or greater before the All-Star break like the Thunder. In our data set, only 14 of 210 teams have covered the number at that rate before the break. You might think a great covering team, like the Thunder, can continue their winning ways in the second half of the season but you’d be wrong.
Combined the 14 teams that covered 60% or greater were 461-274 (62.7%) ATS before the All-Star break. Down the stretch these same teams went 186-205 (47.6%) ATS.
Regression comes for the worst teams as well. This is good news for the Minnesota Timberwolves who have gone 18-33-2 (35.3%) ATS, the least profitable team in the league this season. In the past sevens seasons, teams that covered 40% or less of games before the All-Star break managed to hit 54.1% against-the-spread after the All-Star game.
Many factors contribute to this ATS regression but the primary influence is adjustments made by the oddsmakers. Sportsbooks know which squads the public wants to bet on and against, usually this correlates with a team’s against-the-spread winning percentage. The bookmakers then inflate the lines accordingly making it more difficult for good ATS teams to cover and easier for bad ATS teams to get to the ticket window.
With the second half of the NBA season tipping off, remember that a team’s against-the-spread record is not predictive. Post-All-Star break regression is coming for both the best and worst ATS teams in the league.