Updated

The Arizona Cardinals have switched quarterbacks. Their sieve of an offensive line shows no sign of improving. They have scored a combined 19 points in the last two games. They rank 31st out of 32 NFL teams in offense.

Clearly, the Cardinals must lean on their defense now more than ever.

As they head to Minnesota to face the surprising Vikings, the Cardinals are the only team in the NFL not to give up more than 21 points in a game this season. That is, Arizona defensive coordinator Ray Horton says, the most significant of all defensive stats.

"Really that's probably the only stat that should be measured," he said after Friday's practice, "because you can skew them by yards because when you're ahead by 42 points or whatever the case may be, it's not really a justification of what is the best defense. Obviously, the deal is whether you score more points or less points than they do."

The defense has been consistently effective despite a string of injuries to important players.

Tackle Darnell Dockett sat out the Miami game because of a hamstring injury, only the second game he has missed in his pro career. One of the team's defensive leader, Dockett wasn't particularly effective in the two games since then but says he's at full strength for this one.

Strong safety Adrian Wilson sat out the Philadelphia game with ankle and groin injuries, ending a streak of 62 consecutive games played.

Free safety Kerry Rhodes is out against Minnesota because of a back injury.

Cornerback Greg Toler missed the opener while recovering from knee surgery, then went out with a hamstring injury last Sunday against Buffalo and is doubtful for Sunday.

Horton had talked in training camp about the improved depth on defense. It's a belief that's being tested.

"Three months ago we talked about the depth all across the board," Horton said. "Hopefully, we're built where we're not a house of cards, where if one guy gets hurt it's doom and gloom, and I don't think we are built that way."

The Cardinals' defense ranks 10th in yards allowed, the offense is 31st in yards gained.

Yet questions that even vaguely compare the two units are not appreciated by at least some of the defensive players.

"I'm tired of people talking about defense this and defense that," Dockett said. "At the end of the day we're a team. They (the offense) have a job to do and we have a job to do. We've got to just continue to play together and not listen to people talk about defense, defense has got to be the backbone — defense, defense, defense. Man, we're a team."

The Vikings matchup features 4-2 teams, although the Cardinals have lost consecutive games at St. Louis and at home against Buffalo, a team they were favored to beat by nearly a touchdown. They go to Minnesota a decided underdog.

Inside linebacker Paris Lenon knows from 10 years of NFL experience that once one unit starts pointing fingers at the other, things go downhill in a hurry. Yet this defense, he acknowledges, has developed a sense of pride.

"You can't have us versus them," Lenon said. "We are the Arizona Cardinals, collectively. It's not the Arizona Cardinals defense and Arizona Cardinals offense. We're a team. We win as a team, we lose as a team. But we realize we've started something defensively and we want to live up to that standard every week."

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