FOXBORO -- We've been over this. The Patriots run defense has been abysmal. Especially lately.

But why? Is finding the answer as easy as going to the nearest 300-pound defensive lineman in the Patriots locker room to ask him what's going on?

"It starts up front," said former Patriots captain and linebacker Jerod Mayo on Quick Slants The Podcast. "It always starts up front. (Defensive tackle) Malcom (Brown) isn’t playing well. He was getting pushed out of there left and right. They have to fix it . . .



"The D-Line is playing at an F-level. Whether your run defense is good or bad, it starts at the front."



The Patriots have allowed 625 yards on 110 carries in their last five games for an average of 5.7 yards per carry. In their last two? They've given up 284 yards on 34 carries for an average of 8.4 per carry.

Not what you're looking for, as Bill Belichick might say.

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And while the defensive line has been largely to blame at times, the team's recent struggles against the run have been exacerbated by explosive gains that have come a result of failures at all three levels of the Patriots defense.

In games against the Dolphins and Vikings, the Patriots allowed six runs of 16 yards or more that have completely decimated their rush yards allowed per carry averages.

Consider this: Outside of those six runs, the Patriots have allowed 110 yards on 28 carries over the last two games. That's an average of 3.9 yards per carry. They'd take that.

If you wipe out just those six plays, their 5.7 yards allowed per carry over the last five games drops to 4.3. (The No. 12 run defense in the league, Tennessee, has allowed 4.4 yards per carry this season.)

The Patriots obviously can't wipe away those six long runs, but they can be useful for identifying what has ailed their run defense in spurts.

FIRST QUARTER, FIRST AND 10, PATRIOTS 43-YARD LINE

On Frank Gore's 36-yard run Sunday, the Dolphins ran an interesting play where they pulled their right guard and right tackle with their tight end on the left side blocking up to the middle linebacker (Elandon Roberts) on the second level. Dont'a Hightower was kicked out by the pulling guard, and Devin McCourty was wiped out by the pulling tackle following behind. Things broke down here when Laremy Tunsil (No. 78) controlled Malcom Brown, driving him back and turning him toward the middle of the field. That opened a lane for the pullers to execute their blocks, and there was no one to stop Gore until he was steered out of bounds by Duron Harmon. Good scheme by the Dolphins, but stronger play at the point of attack by Brown could've stopped this one before it started.

SECOND QUARTER, FIRST AND 10, DOLPHINS 46-YARD LINE

The Dolphins had another interesting blocking scheme cooked up on Brandon Bolden's 54-yard touchdown. The Dolphins center left Brown alone and headed immediately to the second level to seal off Roberts, allowing the right guard to down block on Brown. (It functioned almost like a "trap" play, where a guard typically pulls to take out an unblocked defender.) When the right guard blocked down, that left Lawrence Guy unchecked at the line briefly, but the tight end to the play side ended up ear-holing Guy. That "wham" block, combined with the right tackle kicking out on Kyle Van Noy, gave Bolden the lane he needed to get started. The key to the play, though, was Kenny Stills' block on Patrick Chung. Stills worked across Chung's face before Chung could react, sealing off Chung's inside shoulder. With the center blocking Roberts, that alley turned Bolden's four or five-yard gain into something much bigger. From there, Bolden beat Duron Harmon's angle to the sideline and he went untouched into the end zone. Could the front have played this better? Sure. But the play from the secondary turned a good gain into a game-breaking one.

FIRST QUARTER, FIRST AND 10, VIKINGS 45-YARD LINE

Ever heard the NFL referred to as a "copy cat" league? This is why. This is where the Dolphins got the play that resulted in Bolden's long score. Stole it right from the Vikings game plan the week prior. The center got to the second level to block Roberts. The right guard blocked down on Brown. Guy was on the receiving end of a "wham" block from the play-side tight end. The right tackle kicked out on Van Noy. There was the running lane to get things started. One difference here? Chung is playing the deep half of the field. He's not walked up to the linebacker level as he was in Miami, and he's able to eventually steer Dalvin Cook out of bounds because of it. (Had Chung been at the second level and gotten blocked by receiver Laquon Treadwell, this might've been a 55-yard touchdown.) J.C. Jackson, in coverage on Treadwell, had a shot to make this play sooner because Treadwell helped the center on Roberts. Jackson, though, assumed his man was running a route. He was oblivious to Cook running with the football until it was too late.

THIRD QUARTER, SECOND AND 10, DOLPHINS 37-YARD LINE

Ramon Humber played just two defensive snaps against the Dolphins. This was one. Coming from the second level, he charges downhill to fill the "A" gap to the left of the center. When the right guard (No. 77) pushed Brown off the line, it allowed the center to easily dispose of Humber. There was no one there to cut down Gore until Devin McCourty met him 16 yards down the field.

SECOND QUARTER, FIRST AND 10, VIKINGS 34-YARD LINE

Cook had two 18-yard runs against the Patriots in Week 14. The first came on a stretch run to the outside where tight end Kyle Rudolph single-handedly blew things up for the Patriots linebacker level. He turned Van Noy inside and then got Hightower to run into Van Noy's back. Two-for-one. Kirk Cousins faked a flare-out throw to Stefon Diggs on the back side that held Roberts and Chung for an extra beat, allowing Cook to easily follow his blocks well into the Patriots defensive backfield. Jason McCourty was handled by the right tackle and Devin McCourty made what might've been a touchdown-saving trip-up just before getting blocked by the center.

THIRD QUARTER, FIRST AND 10, PATRIOTS 40-YARD LINE

Brown wanted an illegal hands-to-the-face penalty here, and it's hard to tell from this angle if there should've been a call made. Regardless, Cook cut back off of Brown's inside shoulder and across the grain, allowing the left tackle to wipe out Roberts (who fell when he tried to reverse course with Cook). Good individual play there by Cook to take advantage of a front and secondary that over-pursued. His vision allowed him to get all the way to the sideline untouched 18 yards down the field.

To sum up, on the six runs that sent the Patriots run defense from mediocre to miserable -- according to the averages -- there was plenty of blame to go around.

Miami's 36- and 16-yarders might've been snuffed out by better play up front. Minnesota's two 18-yarders were sprung when the Patriots linebacker level was blocked easily. On the two "wham" plays, the secondary could've limited those gains significantly.

On the bright side for the Patriots, if they eliminated those six runs, suddenly the run defense wouldn't look like such an issue. And the Steelers aren't exactly world-beaters when it comes to running the football (25th in yards per carry).

But there have been enough letdowns by the Patriots in enough areas on those explosive run plays allowed that it could take some time to fix the problems. It should come as no surprise then that those issues are at the top of the to-do list for defensive play-caller Brian Flores.

"The run game’s been something that we need to do a much better job of coaching, do a better job of playing," Flores said. "We’ve got to do a better job of getting off blocks, got to do a better job with our angles in the secondary. It’s something we’re going to spend a lot of time on. It’s something we have spent a lot of time on. Teams are going to keep running the ball or attempting to run the ball until we do something to stop it. Obviously, that’s at the top of my priority list and our priority list as a defensive staff."

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