The New England Patriots young offensive line performed admirably in the season opener after spending the preseason as a source of constant criticism, but that game was merely a warm up for the test the unit will face this week against the Cardinals.

Arizona features one of the better defensive lines in the league and ends Darnell Dockett and Calais Campbell, who combined for 13 quarterback hurries against the Seahawks last week, should let everyone know if Tom Brady's security needs to be upgraded.

"They have a very disruptive front -- Dockett and Campbell are really impressive players," Brady said. "It's a very physical team, they're fast. I'd say that they're just very disruptive."

That disruptiveness could prove problematic for an offensive line that is currently in a state of flux. Guard  Dan Connolly returned to practice Thursday after suffering a concussion against the Titans. If he is not ready for Sunday, Donald Thomas, who has totaled 123 career snaps, could be forced to start.

Under normal circumstances Connolly's ailment wouldn't be cause for panic, but tackle Sebastian Vollmer (back), who was limited to 34 of 67 snaps against Tennessee, and guard Logan Mankins (knee) are still less than 100 following offseason surgery.

"Surviving," Mankins, who reportedly played with a torn ACL all of last season, said when asked how he's holding up. "I've been through this a lot, so I know what it takes to get your body to play the season, and we're still working on it. Progress, week-by-week."

To keep Brady safe, the rest of the unit will need to be doing more than just surviving this week.

Defense gaining confidence: The Patriots defense is walking a bit taller this week after limiting the Tennessee Titans to 284 yards last week, including just four rushing yards to Chris Johnson. The team now believes it can come together as one of the better units in the league after finishing as one of the worst in league history last season.

The key to a successful turnaround? Believing that it's possible.

"We have a bunch of great guys on this defense. A lot of guys have a love for the game and a passion for the game," defensive tackle Vince Wilfork said. "Every year that's the goal. When you have a bunch of guys fighting for one goal, and the passion and love for it and understanding of the game, and what needs to be done, you can do mainly anything you want to do, if you put your mind to it. That's what we have." 

Practice report: Connolly returned to practice and was limited during Thursday's session. Limited: CB Alfonzo Dennard (hamstring), TE Daniel Fells (shin), OL Nick McDonald (shoulder), OL Sebastian Vollmer (back), CB Sterling Moore (knee), RB Shane Vereen (foot). Full participant: S Patrick Chung (shoulder).

Nick Underhill covers the Patriots for MassLive.com. Follow him on Twitter @CBSPats or @nick_underhill.