Three-point stance: Arizona Cardinals

CardinalsThe New England Patriots' home opener features the Cardinals, an opponent whose quarterback situation has been unsettled since Kurt Warner took Arizona to Super Bowl XLIII. John Skelton was named Ken Whisenhunt's first choice in the preseason, but was knocked out of Arizona's Week 1 game against the Seahawks with a low ankle sprain. Skelton's replacement was Kevin Kolb, who went 6-for-8 for 66 yards and the game-winning touchdown pass to Andre Roberts with 4:59 left. Whisenhunt has not yet ruled out Skelton for Sunday's game, but reports out of Arizona indicate Kolb is expected to start. What can Patriots fans expect from the former Eagles quarterback (and the rest of the Cardinals, for that matter)? Here are three areas to watch on Sunday:

1. Kevin Kolb (35.4) ranks 51st in Total QBR among the 57 quarterbacks with at least 300 pass attempts since the start of the 2008 season. Kolb has underwhelmed since signing a five-year contract extension worth more than $60 million, and his relegation to backup status in the preseason is easily explained by a look at his numbers. Statistically, Kolb's splits are consistently mediocre against both four-man pass rushes and extra pressure, suggesting the Patriots' defense has a wide range of defensive play-calling options. Kolb's mobility and pocket awareness are below average, as only nine of those 57 quarterbacks have been sacked more frequently than Kolb. He's had limited success on short throws, ranking third in the NFL with 6.3 yards per attempt under 10 yards since the beginning of last season. However, Kolb's 61.4 completion percentage over that time on short throws ranks 29th in the NFL. The Patriots' defense should have another week to gain confidence as a unit before Week 3's visit to Baltimore.

2. The Cardinals' defense was very aggressive last week, sending at least five pass rushers on 51.2 percent of rookie Russell Wilson's dropbacks. Though this approach was likely inflated due to Wilson's rookie status, in 2011 Arizona sent extra pressure on 40 percent of dropbacks. The Cardinals were the league's sixth-most aggressive defense, and Arizona's commitment to extra pressure has generated results since the beginning of last year. The Cardinals have 26 sacks using at least five rushers, tied for most in the NFL, and average a sack every 10.7 dropbacks (sixth-best in NFL). Three rushers had at least six sacks for the Cardinals last year, with all six of Daryl Washington's sacks coming on rushes of at least five defenders. The Cardinals may get creative to pressure Tom Brady. Washington, Calais Campbell and Sam Acho will present a good test for the Patriots' offensive line Sunday. The Cardinals' secondary features some veterans familiar to Patriots fans, including former Steeler William Gay and former Jet Kerry Rhodes.

3. One other member of the Cardinals' secondary is cornerback and All-Pro punt returner Patrick Peterson. Peterson, the fifth overall pick in the 2011 NFL draft, started all 16 games at cornerback last year and is a rising star in the Arizona secondary. In the return game, Peterson turned in one of the best seasons for a returner in NFL history. Peterson had four punt return touchdowns last season, tied with Devin Hester, Rick Upchurch and Jack Christiansen for the single-season record. The Patriots are one of only four teams in the NFL to have not surrendered a punt return touchdown since 2007 (Jaguars, Jets and Buccaneers), but Peterson will challenge that Sunday.