SportsInsights – an American provider of sports betting analytics software – have made an interesting observation on Monday Night Football line betting. They used their betting analysis tool Bet Labs to test the theory that the national spotlight which comes with Monday Night Football encourages teams to try harder. Many pundits theorise that, with the entire football community watching, players put in extra effort to showcase their skills. This causes the favourite to cover the line with greater frequency than in other fixtures.
What is Monday Night Football?
For those who aren’t familiar with the NFL, the biggest fixture each weekend in terms of media attention is Monday Night Football (aired Tuesday Morning AEST). The show blends sports with entertainment and features various panels of analysts before, during and after the game. Many kids in the US grow up with the dream of one day playing on Monday Night Football, so it’s a big deal to be part of it. This is in contrast to Sunday afternoon games in particular, when numerous games are played simultaneously.
Principal–agent problem in line betting
Obviously, the goal of any professional sporting team is to win, rather than cover the line. In sports betting this creates a principal–agent problem, because the team’s incentives aren’t fully aligned with the needs of someone backing them at the line. For example, a side may very well be capable of covering a -10.5 line, but with the clock dying down in the fourth quarter, a team with an 8 point lead will “take a knee” to run out the clock 99 times out of 100.
Extra effort theory
The theory being tested here is whether Monday Night Football better aligns the favourite team’s incentives with the punter. Rather than just win, the players will want to win well, knowing that the rest of the league is watching. As a team they will look to beat the underdog by a clear margin to send a message that they are title contenders. As individuals, the players will want to play well in front of other team coaches and scouts. Players often bounce around from one team to another, so Monday Night Football provides a good platform for them to showcase their skills.
The theorised result of these incentives is that the favourite will cover the line more often in Monday Night Football than in other fixtures. Note that this theory assumes that bookmakers don’t (adequately) adjust the lines already to account for the additional spotlight on the game.
Yes, the underdogs will be putting in extra effort as well, but the theory is that the favourite has better control over the line betting outcome.
Data analysis
Using the Bet Labs System with Pinnacle Sports line data from 2005 onwards, SportsInights tested whether the favourite covered the line with greater frequency in Monday Night Football than in other fixtures during the week (Thursday & Sunday). They then tested 3-point favourites and above separately from 7-point favourites and above to see if a link exists between the level of favouritism and covering the line. Below are the results:
| Monday Night Football | All Other Games | |
|---|---|---|
| All Favourites | 76-63 (54.7%) | 933-967 (49.1%) |
| 3-point Favourites and Greater | 67-52 (56.3%) | 750-803 (48.3%) |
| 7-point Favourites and Greater | 29-18 (61.7%) | 299-322 (48.1%) |
As shown in the table, the favourite covered the line on Monday Night Football 54.7% of the time, compared to a 49.1% in games during other days of the week. This suggests that the extra effort theory holds true.
Furthermore, it appears that the bigger the bookmaker’s line, the more likely the favourite will cover it. Since 2005, 7-point favourites and above covered the line a whopping 61.7% of the time. However, note that this result comes from a smaller sample size.
Interestingly, the Monday Night Football line results are in contrast with NFL games at other times during the week, where 3-point favourites only cover the line 48.3% of the time while 7-point favourites are marginally worse at 48.1%.
Note that with 1.90 line odds, a punter needs a 52.356% line betting record to break even. With 1.952 Pinnacle Sports line odds the required hurdle rate is 51.230%. This indicates the impact of the extra effort theory is enough for +EV line betting IF bookmakers haven’t made the adjustment.