San Francisco 49ers beat Arizona Cardinals, 20–16

The 49ers closed as 5-point underdogs and won outright. The betting market gave them a 32% chance.

It was the biggest of 3 NFL upsets in 2009 Week 1, and the 29th-biggest of the 2009 season. San Francisco 49ers pulled off 1 other upset in 2009.

Other NFL upsets in 2009 Week 1

1. Denver Broncos 12, Cincinnati Bengals 7

   4.5-point underdog33% to winRecap
   Upset size4.5
2. New York Jets 24, Houston Texans 7

   4.5-point underdog32% to winRecap
   Upset size4.5

San Francisco 49ers’ other 2009 upsets

1. San Francisco 49ers 24, Arizona Cardinals 9

   Week 144-point underdog35% to winRecap
   Upset size4

More: San Francisco 49ers upsets · Arizona Cardinals upsets · all Week 1 upsets · how upset size works