The St. Louis Rams' 4-4 record outside the NFC West has helped them rise to the top of the division standings.
Seattle's 3-1 record inside the division has been key.
Going into the season, games against AFC West teams appeared pivotal for teams from both divisions. Neither division appeared particularly strong. The possibility existed for teams to pad records against weaklings from the other division.
That has happened, to an extent, at least for the 2009 last-place teams from those Western divisions. Kansas City's 7-4 overall record includes a 3-0 mark against the NFC West. The Rams' 5-6 record includes going 2-1 against the AFC West.
Kansas City and St. Louis play at the Edward Jones Dome in Week 15. A Rams victory would leave each team with a 3-1 record against the other's division.
The San Francisco 49ers, meanwhile, can blame their third-place NFC West standing on an 0-4 record against the NFC South. They lost to New Orleans on the final play. They lost to Atlanta on a field goal with two seconds remaining. They lost to Carolina on a field goal with 39 seconds left.