NFL odds, Week 6: Arizona Cardinals open, continue as huge underdogs vs. San Francisco 49ers

The Arizona Cardinals are not very popular for sports books in Las Vegas. This is evidenced by the fact that this week, the sixth in a row, Arizona opens as an underdog. So far, the Cardinals have performed well against the spread. They are 4-1 this season against the Vegas spread, while their real record is 3-2.

Against the San Francisco 49ers, the team the Cardinals will play on the road this weekend, Arizona again opens as an underdog -- big underdogs.

The line opened at 9.5 points in favor of San Fran, with the over/under set at 42.

Since then, the line has moved to as much as 11.5, with the over/under dropping slightly to as low as 41.

What does this mean for those who like to bet on football?

Personally, that spread seems very high. I get why -- San Francisco is still a public team in betting terms. They get wagers on their side just because of who they are. They have a reputation still of being a Super Bowl contender. On the other hand, Arizona is the exact opposite in terms of reputation and popularity. The line has to be set high to get any money on the Cardinals' side.

Seeing the way the Cardinals have played all season, unless their defense falls apart, you have to imagine that it will be a close game. Even in a Cardinals loss, it will probably be no more than 10 points. Likewise, if both defenses are playing as they have, it will be a low scoring game.

Which way do you go? If it's my money, I am hitting the under and I'm taking the points and the Cards.

More from Revenge of the Birds:

• 2013 NFL picks: ROTB writers make their Week 6 winner selections
• Panthers vs. Cardinals review: Calais Campbell defense’s biggest star, Rob Housler awful according to PFF
• Panthers vs. Cardinals review: ROTB podcast talks Levi Brown trade, Carson Palmer problems, more [podcast]
• Cardinals vs. 49ers: Under the radar players to watch
• Carson Palmer, the NFL's most 'meh' quarterback