How Has Jim Schwartz Revamped the Buffalo Bills Defense?

Jim Schwartz's feet came off the ground. He raised his fist into the air as his defense hoisted him onto its shoulders and carried him off of Ford Field following the Buffalo Bills' 17-14 victory over the Detroit Lions.

It was a controversial moment, one that ESPN.com's Michael Rothstein reports has sparked a harsh response from Lions wide receiver Golden Tate, but Schwartz has earned the respect of his team.

Through the first five games of the season, he has his defense playing some of the best football we have seen in Buffalo in years.

Year	Coordinator	Points	Yards	Pass D	Run D
2010	George Edwards	28	24	3	32
2011	George Edwards	30	26	19	28
2012	Dave Wannstedt	26	22	10	32
2013	Mike Pettine	20	10	4	28
2014	Jim Schwartz	5	8	20	2

The Bills haven't seen a defense this good since the first term of the George W. Bush administration.

Most folks—including yours truly—didn't see it coming. There was concern that the defense's success under Mike Pettine was more attributable to the scheme than the personnel. Thus far, that is not proving to be the case.

"It's been going very well," head coach Doug Marrone said of the transition from Pettine to Schwartz. "Obviously, Jim is a great communicator and has done a great job with the coaches on the defensive side of the football. Also, the players, I think they play extremely hard for him and understand what we're trying to get accomplished."

Through five games last season, the Bills sent an extra defender (subscription required) after the quarterback on 79 of 213 pass plays (37.1 percent). This season, that number is down to 39 of 216 plays (18.1 percent).

The strength of their front four has allowed the rest of the defense to drop into coverage, tightening up the windows in the passing game.

Credit: NFL Game Rewind

This is essentially a four-man line with Jerry Hughes in a two-point stance opposite Mario Williams, with defensive tackles Stefan Charles and Marcell Dareus on the inside. Generally, Kyle Williams is the one lined up next to Dareus, but Williams was out last week with a knee injury.

Hughes may be in a two-point stance like a linebacker, but he is truly a defensive end in the Bills defense. He has dropped into coverage on only six of his 219 snaps (subscription required) this season.

Notice how Hughes and Williams are lined up wide of the formation. This is called a "Wide 9" alignment, with the defensive ends spread out to help them get around the offensive tackle. This scheme works well with two explosive ends like Hughes and Williams who can get to a tackle's outside shoulder quickly off the snap.

Dareus ended up with a sack on this play, with the defensive ends providing some pressure that forced Stafford to step up slightly in the pocket.

The defensive line earns its headlines with its pass-rushing ability, but its solid work against the run has been the hallmark of the team's defensive turnaround.

Credit: NFL Game Rewind

On this draw run by Lions running back Reggie Bush, the Bills came out in a nickel front. This would ordinarily be a favorable look for a running play, with six defenders trying to account for seven gaps.

Credit: NFL Game Rewind

There's a bit of a hole between the left end and left defensive tackle, but the run heads to the other side, where the Bills flow to the ball and control their gaps. Linebacker Preston Brown (circled in black) did a nice job to shed the offensive guard and make the tackle on Bush before the running back could reach the line of scrimmage.

Bills head coach Doug Marrone had a simple explanation for the team's improvements against the run: "Communication, understanding from the players and we have good players on defense."

The play of the Bills' front seven has helped them in run defense, and who knows, maybe the less aggressive play-calling of Schwartz from a pressure perspective has put the linebackers in better position to stop the run at the second level.

"The scheme has changed a lot: It was a lot different with Pettine, it was the Jets' scheme, [but] it's a lot different [now]," New England Patriots head coach Bill Belichick said of the Bills defense and how it's changed under Schwartz.

"It was a lot of pressure. They have good players. I mean, look, you've got to block those guys no matter what defense they're in. It's still the same guys that are hard to block. I would say the scheme is quite a bit different. I mean, they had a four-man rush last year, too. I'm not saying that. But there was a lot more pressure."

Opposing offenses have had their hands full with the Bills' front four, and as long as that holds true, Schwartz's defensive scheme should continue to thrive.

Unless otherwise noted, quotes obtained firsthand. Advanced statistics courtesy of Pro Football Focus (subscription required).

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