Cards take on challenging road test.

• Author: Wilner, Barry
• Position: Sports

Byline: Barry Wilner

Arizona (3-0) at Denver (2-1): Both teams are rested coming off byes, but the Cardinals have quarterback concerns with Carson Palmer's shoulder issues. Then again, Drew Stanton has stepped in and won his two starts.

The Cardinals' defense must remain stingy -- 45 points allowed thus far, none in the fourth quarter -- and that's a prodigious challenge against Peyton Manning, who already has thrown for eight touchdowns. He needs one more for 500, a number only Brett Favre has reached.

The Broncos fell at Seattle in their last game before a bye, and beat Indianapolis and Kansas City before that.

''It's a big road game against a team that went to the Super Bowl last year and is going to be a playoff team this year,'' Cardinals coach Bruce Arians says.

''It's a good barometer for us on the road. ... We didn't play any slouches so far. There are no slouches in this league. This is a really good ballclub with an outstanding defense and kicking game, and a crowd. All the factors that go into playing at Denver are a huge advantage (for them).''

Houston (3-1) at Dallas (3-1): For the Lone Star state title, but more importantly, the winner solidifies its standing in its division.

The Texans lead the AFC South and the Cowboys are tied atop the NFC East, both surprising developments, although it is early.

Perhaps the two most valuable players through one month will be on the field: Texans defensive end J.J. Watt and Cowboys running back DeMarco Murray, the league's leading rusher.

Kansas City (2-2) at San Francisco (2-2): Each team comes off an impressive win, and the spotlight surely will be on Chiefs QB Alex Smith's return to the Bay Area.

The top overall draft pick in 2005 by the 49ers got his career on track under Jim Harbaugh in 2011, then lost the job to Colin Kaepernick after Smith sustained a concussion.

He landed in Kansas City and guided the Chiefs to the playoffs last year.

''No bitterness at all,'' Smith says. ''What happened there the end of the (2012) year, losing my job, you get to that point and I say this a lot, worrying about anything that was outside your control and dwelling on any of that stuff is only going to have a negative impact.''

Chicago (2-2) at Carolina (2-2): Each team comes off a forgettable loss.

Chicago malfunctioned after halftime at home against Green Bay, and its depth is being tested by a slew of injuries. But the Bears are 2-0 on the road.

Something has gone terribly wrong with Carolina's...