Three is magic number

Slowed by a toe injury, running back LaDainian Tomlinson is not the same breakaway threat this season, and the San Diego Chargers are staggering to the midpoint of the season.

The New Orleans Saints, minus injured running back Reggie Bush, are in a similarly poor condition.

The Chargers and Saints both are 3-4 going into their game today in London. It shapes up as a quarterback duel between New Orleans' Drew Brees and San Diego's Philip Rivers, former Chargers teammates.

The Chargers are 3-point favorites -- the line is 31/2 at a few sports books -- but handicapper Andy Iskoe is siding with the Saints.

"Based on what these teams have done this season," said Iskoe (thelogicalapproach.com), "this game should be about a pick'em."

How important is the line? Every football bettor has heard that 3 is the key number in NFL wagering, and Iskoe has done research that supports the theory.

In 6,222 NFL regular-season games since 1981, 970 games (15.59 percent) were decided by 3 points. "The number 3 is the most frequent number, and it has been the most common number every year," Iskoe said.

To put it in perspective, the next most common number is 7, and that has landed 501 times (8.05 percent).

"If you put those two together, that's nearly one game in four (23.64 percent) that has landed on 3 or 7," Iskoe said.

Of the 102 games this season, 13 (12.75 percent) were decided by 3 points. So this season's results are below the historical average.

Using a 6-point teaser to drop a favorite of 6, 7 or 8 points below the key number of 3 is a popular strategy of NFL bettors. But a 3-point favorite has won by 3 points in only two games this season.

The Denver Broncos were 3-point home favorites in a 16-13 win over the Tampa Bay Buccaneers on Oct. 5. The line on the Broncos moved to 31/2 just before kickoff. The Carolina Panthers were 3-point home favorites in a 20-17 win over the Chicago Bears on Sept. 14. The Bears have been favorites or underdogs of 3 or 31/2 points in six consecutive games.

The Chargers have been favored in six of eight games this season. Two games closed as a pick'em. This is the first time they have been favored by fewer than 6 points, and none of their games was decided by 3 points.