Statistically, the average bettor tends to bet favorites. That is a big mistake, and here’s why.
First, the average bettor tends to overstate the relative strength of the league’s better players and teams. What pro handicappers know is that there is actually tremendous parity in the league, with not that much difference between the best player at a position and the worst.
When a team of slightly worse players is more motivated than a team of slightly better players an outright upset is possible. Most certainly, it’s possible for the “inferior” team to cover the point spread.
Second, the point spread tends to nullify any obvious scrimmage edge (skill or power advantage) a team has over its opponent. In the 1999 and 2000 seasons, for example, there were 167 games in which the point spread was seven points or more (games where one team’s advantage over another was perceived to be sizable). While the underdog won just 36 of these games outright (21.6 percent), the underdog covered the point spread in 83 of the games (while tying it in six): a success rate of 51.6 percent.
Third, by betting an underdog, you have an important element of game strategy on your side. NFL teams do their best to win a game. Therefore, in the last few minutes of a game, a team that is leading seldom takes much risk to score more points. Instead, it concentrates on hanging on to its lead. The team that is losing, on the other hand, usually tries to score until the bitter end. If a bettor has taken a favorite that is ahead but not covering with five minutes or less to go, that bettor is in trouble.
In 20 years of handicapping the NFL, I have yet to come across a long-term winning bettor who does not bet mostly underdogs.