One of the biggest surprises with the New England Patriots this season has been the defense failing to be a top-10 unit. Historically, they have ranked amongst the best in the NFL, but things have been different under first-year defensive coordinator DeMarcus Covington.

The Patriots rank 22nd in total defense on the year and have given up 344.8 yards per game. The unit itself has been marred by injuries and inconsistent production. With that being said, they managed to keep many of the same players on the roster from last season.

"Yeah, I would say every year is different. Every defense is different. So that's kind of how I look at it. Like I wouldn't read too much into it," said Covington, via Boston Herald's Doug Kyed. "So for us, we're just trying to do the best we can every week, us as a coaching staff, us as the players, and I think those guys are working hard and trying to do what we ask them to do.

"So, I look at each year being different. So, like what you did last year, what we did previous years, every year is different. So that's kind of how I look at it."

The Patriots have productive pieces on the defensive side of the ball, such as cornerback Christian Gonzalez. Defensive tackle Christian Barmore has also been a standout playmaker for the unit, but he is currently on the reserve non-football illness list.

The good news is the Patriots will enter free agency with more salary cap space than any team in the NFL. So they should have plenty of money to spend to make the necessary upgrades.

Improved coaching could help shore up some of the other issues for the unit. It's the only way the team will have a shot at becoming a top-10 defense again.

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