How much every NFL QB is worth against the spread

Patrick Mahomes has had an incredible season so far and is an MVP candidate. AP Photo/Charlie Riedel

While Kansas City's Patrick Mahomes is the consensus favorite to win the NFL MVP, Aaron Rodgers and Tom Brady are the most critical quarterbacks to a point spread. That is the opinion of one respected Las Vegas oddsmaker.

Ed Salmons of the SuperBook at the Westgate says he would adjust the line by eight points if either New England or Green Bay started its backup quarterback. Mahomes leads the league in passing yards and touchdowns, but Salmons would only move the spread five points if backup Chad Henne played.

"I think [Mahomes is] awesome. I'm not going to take anything away from him, but I think the Chiefs team is just so deep, it's hard to really screw that up," Salmons told ESPN. "I'll give the Chiefs credit just because I don't think Henne is a total stiff."

However, he does not feel Green Bay is as fortunate. "It's hard to get a worse backup quarterback than [Deshone] Kizer because he just can't play without making mistakes. If the backup were Colt McCoy, then Rodgers wouldn't be worth as much," Salmons said.

Formulating a player's exact worth is much more complicated than simple math. The nuanced process hinges on the original game line because NFL oddsmaking relies so heavily on the key betting numbers of three, four, six and seven -- common margins of victory.

"The higher these spreads go, the more [the adjustment] scales back," Salmons said. "The points mean more at low numbers and less at high numbers. That's just how it works."

ESPN asked Salmons to assess a point spread for every team playing on the road against the Rams, which are his highest-powered team. Then, he determined a point spread with the team's backup QB in the exact same situation. Below are the tiers of line changes, given the backups. As for the Rams, they would hypothetically host San Francisco.

Here is how much every starting NFL QB is worth against the number: