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One thing you can count on from the New England Patriots every year is that they will get better down the stretch.

An area that is a weakness early in the season may not become a strength by season's end, but you can bet that Patriots head coach Bill Belichick will find some way to mitigate the problem.

Early in the season, it looked like the run defense might be the one area where the Patriots could be exposed. It was a surprising turn of events, considering that they invested so heavily in the front seven to make that the strength of their defense after losing so many key pieces in the secondary.

The Patriots allowed 100 rushing yards or more in four of their first five games, including 134 to the Pittsburgh Steelers and 160 to the Buffalo Bills.

Sure, the Patriots were inviting the run at times—due in part to the massive leads they had built in some of those games—but only recently have we finally begun to see the potential of the Patriots defense against the run.

Eighty-nine yards against the New York Jets. Fifteen yards against the Miami Dolphins. And these were teams that came into the game hoping that they could run it down the throats of the Patriots and help control the clock to put the brakes on the Patriots offense.

In the process, some key players have stepped up. Namely, defensive tackles Dominique Easley and Malcom Brown have made "good progress," according to Belichick:

Starting with Easley, just his opportunity, the fact that he's been out on the field and has participated in everything so much more than he was able to do last year, just really no comparison, and of course all that fundamental work in training camp and all the practice reps both against our offense and working with teammates on defense in terms of communication and all that. It's been very valuable. I think that his explosiveness, quickness, ability to be disruptive on plays where he can get into the backfield and penetrate the line of scrimmage has shown up on a number of occasions. And also Easley has helped us a little bit on the punt return side of it. He's been disruptive doing that the last couple weeks. Malcom Brown has really pretty much just played one position, but that’s gotten progressively better. He’s strung together now a couple consistent weeks, and that's good.

Easley has been helped by a run of good health the likes of which he hasn't had in years as he's dealt with one knee injury after another. He was healthy for the offseason workout program this summer, though, and the practice reps helped him improve his game.

Brown's role hasn't increased as much; the rookie has played between 20 and 35 snaps in each of the Patriots' first seven games so far, and he has been on the field for just 35.7 percent of the defensive plays, according to Pro Football Focus. He's also one of the top 10 defensive tackles in run-stop percentage, making a tackle that constituted a "loss" for the offense on 11.9 percent of run plays he participated.

Some of the improvement is due to the players on the field, and some of it is due to the players not on the field. In Week 1 against the Steelers, rookie defensive lineman Geneo Grissom played extensively at defensive tackle. It would be an understatement to say the 6'3", 252-pounder is undersized for the inside of the defensive line, which might have lent itself to some of the big runs that night.

Patriots defensive line snap counts Player Games Snaps Snap % (in games played) Chandler Jones 7 432 87.1 Rob Ninkovich 7 422 85.1 Jabaal Sheard 5 206 57.9 Malcom Brown 7 177 35.7 Sealver Siliga 7 165 33.3 Alan Branch 7 156 31.5 Dominique Easley 6 146 34.4 Geneo Grissom 6 82 19.7 Akiem Hicks 4 70 23.8 Source: ProFootballFocus.com

That being said, the linebackers have been the real dominant pieces on the Patriots defense. Jamie Collins and Dont'a Hightower are the biggest difference-makers for the Patriots defense, whether it's pass rushing, coverage or stuffing the run. But those two have been consistent all season long.

Really, the Patriots' defensive improvement is less about the individuals and more about the big picture. Their overall depth on the defensive line is incredible. Between defensive ends Chandler Jones, Rob Ninkovich and Jabaal Sheard, defensive tackles Akiem Hicks, Dominique Easley, Malcom Brown, Sealver Siliga and Alan Branch, the Patriots have enough bodies to rotate in fresh legs on a frequent basis.

That might help explain why so many Patriots defensive linemen are below 50 percent in their total snap counts this season. Keeping fresh bodies on the field helps the defensive line hold stout at the point of attack, preventing those holes from opening up.

Individual improvement and a deep talent pool are the keys to the Patriots finally finding their stroke in run defense.

Unless otherwise noted, all quotes obtained via team news release.