Patriots' decimated defense

The cornerback combo of Darius Butler and Devin McCourty has not held up for the Patriots. US Presswire

If there's anything that can dramatically affect the performance of an otherwise dominant NFL team, it is injuries. If there's any team that knows how huge the impact of injuries can be, it's the New England Patriots. It was about nine years and one week ago that Tom Brady made his first start as the Patriots quarterback, a move that came about after Drew Bledsoe suffered a sheared blood vessel in his chest. The injury famously helped catapult the Patriots into the Super Bowl and gave Brady a chance to become a superstar. Seven years later, Brady's Week 1 knee injury turned over the starting job to Matt Cassel, and the Patriots promptly went from 16-0 to out of the playoffs.

This year, it's not injuries to Brady or any of the offensive players that have dramatically impacted the Patriots. Instead, it's the defense that has been riddled with injuries. A unit that ranked 16th in defensive DVOA last season has fallen to 27th in the league through three weeks. It has allowed more than 27 points per game against three teams -- the Cincinnati Bengals, New York Jets and Buffalo Bills -- that have averaged 15 points per game when not playing the Patriots. Once DVOA starts factoring in opponent adjustments as the season goes along, it's entirely possible that the Patriots could end up with the worst defense in football.

Is there hope for New England? What's been the most troubling injury for the Pats? What does history say about their chances of improving?