NFC West injury report: Kevin Kolb, Joe Staley injured in Week 6

Arizona Cardinals quarterback Kevin Kolb assumed the starting job in Week 1 of the season after an injury to John Skelton, but the two quarterbacks reversed roles in Week 6. Kolb, who has started every game for Arizona since that point, was injured in the fourth quarter of Arizona's loss to the Buffalo Bills on Sunday when he was sandwiched by two defenders on a scramble.

Kolb appeared to be in a lot of pain and left the game with a rib injury. The quarterback has undergone X-rays on the injury, the results of which should be revealed sometime Monday afternoon. Based on what transpired on the field on Sunday after the hit, it would not be a surprise if Kolb was forced to miss several games.

He wasn't the only Cardinal injured on Sunday. Arizona also lost starting safety Kerry Rhodes for the game, who was carried off the field after injuring his back. Cardinals coach Ken Whisenhunt said after the game that Rhodes' back "locked up," and that the injury likely isn't serious.

The San Francisco 49ers were embarrassed on Sunday by the New York Giants, and they also lost left tackle Joe Staley to a concussion. It's unclear how many games Staley, a Pro Bowler in 2011 who also suffered a concussion last season, will miss.

The St. Louis Rams and Seattle Seahawks both managed to escape Sunday's action with no major injuries.