Aaron Rodgers’ collarbone injury is sending shockwaves through the league. One of the NFL favorites to win the Super Bowl has now fallen to probably not making the playoffs if Rodgers indeed misses the rest of the year.
According to David Purdum, the injury initially moved the line for next week’s game in Green Bay by a whopping 10 points. Green Bay was a 6.5 point favorite in an early line at Westgate and that has now been reversed to New Orleans being a 3.5 point favorite on the road with Brett Hundley at quarterback.
CG Technology vice president of risk Jason Simbal said, in his opinion, Rodgers is the most valuable player to the line in the NFL, even more than New England Patriots quarterback Tom Brady.
“It’s more about the quality of backups than the difference between Rodgers and Brady,” Simbal said.
Whether you accept that is the entire difference or not, it is a large line movement.
To try to convert that point spread move to what it means in terms of win percentage chances, a line movement of 10 points represents about a 30% swing in chances of winning a game. For example, over the last decade, 6.5 point favorites have won 71.1% of games, while 3.5 point underdogs have won 41.5% of the time.
If you think Green Bay was roughly an 11-win team with Rodgers, and would have gone 7-3 the rest of the way on average, then this move means that the Packers are estimated to go about 4-6 over the rest of the way. Or to put it another way, Vegas views Green Bay, with the same roster other than Rodgers, to be more like a 6-win team over the course of a full season with Hundley.
My estimate, in looking at the actual remaining games, is that Green Bay’s over/under is 3.9 wins in the last 10, with no sure things. Even the game at Cleveland will be closer to a pick ’em on the road, and they will likely be a slight underdog in the next four games before being a big underdog at Pittsburgh (assuming Hundley remains the quarterback and they don’t make any outside moves).
The Westgate already moved the Super Bowl odds from 5-1 to 12-1, and it will shoot higher if he is out for the year.
Let’s try to also put that 10-point move for a quarterback in perspective in going from Rodgers to Hundley.
Two years ago, I looked at situations where a team had multiple quarterbacks start games and no one started more than 10. The dropoff for some key quarterbacks once we adjusted for schedule: Flacco to Clausen/Mallett (9.0 points), Romo to Cassel/Weeden (8.8 points), Roethlisberger to Vick/Jones (7.0), Luck to Hasselbeck (6.6).
Last year, using the same method, Tom Brady was worth 7 more points than his backups (1+ game with Jimmy Garoppolo, almost 3 with Jacoby Brissett).