Quarterback Kevin Kolb has been a surprise hero for the Cardinals in their undefeated start. (AP)

Cardinals at Rams -- Week 5

Where: Edward Jones Dome, St. Louis (FieldTurf)

When: Thursday, 8:20 p.m. ET (NFL Network)

Spread: Cardinals by 1

Forecast: Indoors

Records: Cardinals (Overall: 4-0, NFC West: 1-0); Rams (Overall 2-2, NFC West 1-0)

Past results: Two most recent meetings -- Nov. 27, 2011: Cardinals 23, Rams 20; Nov. 6, 2011: Cardinals 19, Rams 13 (OT). Series record: Cardinals have won 10 of the past 11 meetings and lead 33-32-2 all-time.

What matters: Just when you thought the Cardinals were watching perfection slip from their grasp, Andre Roberts and Kerry Rhodes snatched it right back. Arizona continued its dance with destiny on Sunday after a 24-21 overtime win over the Dolphins, and win after win -- including 11 of 13 dating back to last season -- has the Cardinals playing with peak confidence. The bumps and bruises are piling up, though, so a hurried Thursday night game might be a chore for Arizona.

Who matters: Offensively, despite big gains by Kevin Kolb, who ranks ninth in the NFL with a 97.6 QB rating, the Cardinals have been downright brutal. Ryan Williams is averaging less than 33 yards per game and 3.0 yards per carry, leading receiver Larry Fitzgerald comes in at just over 60 yards per game, and Beanie Wells is down for two months with turf toe. Somehow, all that doesn't matter. With its opportunistic defense, Arizona has been able to avoid big deficits, the offense has stabalized in the fourth quarter, and perfection has been maintained. 

Key matchups: The biggest matchup for Arizona, it seems, are the Cardinals vs. fate. Arizona has knocked on the door of disaster countless times this season but things have seemed to settle down at just the right moment. OK, so fate, and the St. Louis defensive line. The Cardinals have been sieve-like up front, including eight sacks against the Dolphins, and the Rams offer no reprieve with their talented young defensive front.

Injuries of note: Darnell Dockett (hamstring) was sorely missed against the Dolphins, but he'll be a game-time decision against the Rams. He practiced on a limited basis on Monday. The biggest injury concern remains the tight end position, where Todd Heap (knee) and Jim Dray (knee) have left the job to Rob Housler.

Inside stuff: The Cardinals have attacked the ballcarrier with persistence through four games, ranking second in the NFL with 16 sacks and seven forced fumbles and leading the league in fumble recoveries with six. It's those breaks that have helped Arizona turn the tide of undecided games. 

Stats you should know: One reason for the Cardinals' hot start -- the quality, or lack thereof, of the opposing quarterback. In addition to New England's Tom Brady, the Cardinals have defeated Seattle's Russell Wilson, Philadelphia's Michael Vick and Miami's Ryan Tannehill, each of whom are rated 27th or below out of 32 teams in quarterback rating. ... The Cardinals are only averaging 2.7 yards per carry. 

Looking ahead: Arizona has some need to rest up after the Thursday night game, resuming play the following Sunday against Buffalo. Then, a tough task at streaking Minnesota before one of two potentially division-deciding dates with San Francisco.

Prediction: Cardinals 24, Rams 20

For more news and analysis from Cardinals blogger Jon Gold, follow @CBSSportsNFLARI on Twitter.