How much every NFL QB is worth against the spread

Jimmy Garoppolo injured his knee near the sideline late in the 49ers' loss to the Chiefs. AP Photo/Charlie Riedel

A hobbled Aaron Rodgers is more valuable to the point spread than a healthy Tom Brady or any other NFL quarterback. That's the viewpoint of oddsmakers, who define their opinions by their risk of losing millions, rather than clamoring for hot takes in the GOAT conversation.

"New England has always overachieved with a backup quarterback," said Ed Salmons, an oddsmaker at the Westgate Las Vegas Superbook. "Green Bay is in a class [by itself] because they're obsessed with getting horrendous second-string quarterbacks."

Therein lies the root of this discussion. The drop-off from starter to backup plays a definitive role in this conversation as well.

"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.

While Rodgers is still valuable on one leg, other injuries require caution. "Carson Wentz is going to be a guy with a huge knee brace on that's not going to be able to run the way he did last year," Salmons said. "It's hard to give a Wentz number right now because the current version is going to be a lot different than the version of next year when he's 100 percent healthy."

After Baker Mayfield led Cleveland to a 21-17 win on Thursday night, Salmons updated his numbers on the Browns QB situation. "The Browns were getting much worse with Tyrod Taylor, who was a competent QB in his career," Salmons said. "The current version of Taylor is top three bad. Obviously with Mayfield they are a much better team. That's worth three points to me."

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 numbers of three, four and seven -- the most common margins of victory.

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 play at New England, which is the closest team in Salmons' power rankings.