This would seem to increase the 49ers' chances for victory, but based on what? Cutler has a better won-lost record as a starter. He has greater experience running the Bears' offense. But if you're looking for additional evidence, you won't find it in the traditional or advanced stats used to evaluate quarterbacks over time.
2008-Present QB Comparison
Source: ESPN Stats & Information
You'll see a couple of quarterbacks who have produced similarly over the past five seasons. Cutler has played more and for better teams. But his NFL passer rating since 2008 is 83.0, compared with 85.1 for Campbell and 84.1 for every other NFL quarterback. Cutler's Total QBR score since 2008 checks in at 56.5 when 50 is about average and 65-plus represents Pro Bowl-caliber play. The figure was 50.9 for Campbell and 52.0 for all others.
The point is that the 49ers might not be catching a big break while Cutler sits out the game after suffering a concussion in a 13-6 home defeat to the Houston Texans in Week 10. The Bears paid a $3.5 million salary for Campbell to be their backup because they figured they could win with him.
"We feel like he is a starting quarterback in the NFL that we have being our backup, and we feel very comfortable with him leading us," Bears coach Lovie Smith told reporters.
NFC North blogger Kevin Seifert and I discussed on a recent Inside Slant podcast how aggressive the Bears should be in re-signing Cutler after the season. I had some general impressions of Cutler but was curious to see how he stacked up against the highest-paid quarterbacks the past few seasons.
Peyton Manning, Aaron Rodgers, Tom Brady, Drew Brees and Matt Ryan all had QBR scores in the 70s among regular starters over that period. Cutler was at 56.5. The figure for Cutler is 50.3 since 2009, compared with 50.5 for former Bears starter Kyle Orton and 47.7 for Campbell. Again, all the top quarterbacks were closer to 65-plus.
2012 Cutler vs. Qualifying QBs
Source: ESPN Stats & Information
Cutler does have a 31-19 starting record with the Bears. That is far better than the 31-39 mark Campbell has posted for his career. But the Bears were 30-20 in the 50-game period before Cutler arrived. Orton, Rex Grossman and Brian Griese were their starting quarterbacks in that span.
Campbell's former team, Washington, was 31-39 in the 70-game span before Campbell posted the same starting record for the Redskins and Oakland Raiders. Tony Banks, Shane Matthews, Patrick Ramsey, Danny Wuerffel, Tim Hasselbeck and Mark Brunell were the starting quarterbacks during that run.
Quarterback play matters a great deal. Teams with the higher QBR scores have won 86 percent of games since 2008. Teams with higher NFL passer ratings have won 79.7 percent of the time over the same period. Those figures outrank even the winning percentages for teams winning the turnover battle (78.5 percent, a figure related to the previous two in that QBs are leading contributors to turnover stats).
The Bears are most dangerous for their defense, however. They rank among the NFL's top five on defense in passer rating, QBR, yards, rushing yards, net yards per pass attempt, interception percentage, third-down conversion rate and points. They were built to win without great quarterback play.
So, if Cutler has been only slightly above average and Campbell plays an average game Monday night, the drop won't be as pronounced as it usually is when a journeyman replaces a big-name quarterback. And if Campbell plays poorly, well, Cutler has done that, too. He has thrown more than three picks in a game four times since 2008, a league high.