Marcell Dareus and the Bills defense have been dominant so far this season. (Tom Szczerbowski/Getty Images)

NFL purists will tell you that “tanking” doesn’t exist in the sport. With only 16 games and non-guaranteed contracts, there’s no room to not give 100 percent effort every game and every season. In reality, though, general managers routinely make decisions that are detrimental to short-term success in the belief they’ll be better off in the long term.

No team was more brazen in executing that strategy this offseason than the Buffalo Bills. They traded their top returning receiver, Sammy Watkins, to the Rams; dealt their top returning cornerback, Ronald Darby, to the Eagles; and renegotiated quarterback Tyrod Taylor’s contract to one that’s easier to get out from under. You can argue that all three were good moves yet still say they made the Bills worse in 2017.

Except, for some reason, the Bills have not gotten worse. At 3-1, the Bills are almost halfway to their 2016 win total (seven) and sit atop the AFC East. Through four games under Coach Sean McDermott, they’ve allowed only 54 points and are second in the NFL in points per drive. They’re playing better defensively than they ever played under Rex Ryan and look like a serious threat to return to the playoffs for the first time this millennium. So how have they gotten the job done? The answer is simple: by scheming to talent … and acquiring talent that fits the scheme.

The abilities of players in the NFL are often thought of as static quantities. The Madden video games have taught us all that a cornerback with an 85 overall rating is inherently better than one with an 80, and therefore your defense will be better with the former. The truth is, the video game and its players are far more nuanced than that.

Madden had Darby rated at 79 overall heading into this season, the highest of any Bills cornerback and five points higher than Rams cornerback E.J. Gaines (who was acquired for Watkins). Looking through the vacuum of past performance, those were fairly accurate measures. The thing is, Darby’s skill set is almost exclusively that of a man-to-man cornerback. He has incredible makeup speed and can stay in the hip pocket of a receiver up and down the field. When asked to make plays in off coverage, though, he’s a step slow to react, and his 4.3 speed is inconsequential. McDermott’s defense asks his cornerbacks to do far more of the latter than the former. The 2017 Bills pass defense looks a lot like the 2016 Panthers’, McDermott’s old team, in terms of coverages:

Coverage 2016 Panthers 2017 Bills
Man 13.4% 27.3%
Zone 86.6% 72.7%
0 0.2% 1.9%
1 11.7% 25.9%
2 13.2% 17.1%
2-Man 1.5% 2.5%
3 37.3% 34.2%
4 26.7% 22.8%
6 9.4% 7.0%

The 2016 Panthers were the heaviest zone coverage team in the NFL and one of the zone-heaviest teams in recent memory. The Bills have played a bit more man but are still well below the league average of over 39 percent.

Not all zone coverages are created equal, however. When Seattle plays Cover-3, it looks a lot more like man coverage, because the cornerbacks are often locked onto a single receiver. When the Bills play Cover-3, the cornerbacks are off and reading not only the receivers in front of them but also the quarterback’s eyes. The skill sets involved in both could not be more different. Darby had the former but often lacked the latter.

When looking at the defensive backs McDermott targeted this offseason, there’s a clear archetype. Jordan Poyer and Micah Hyde are near carbon copies in terms of skill set. Both are slow by cornerback standards, yet both have exceptional instincts. Ask either to stick with Julio Jones one-on-one, and they’re getting beaten, but tell either to play over the top of a Jones post route, and they’ll meet him at the football. McDermott recognized the skill set and stuck both as the Swiss-army-knife safeties that his defense requires. The results have been outstanding so far: Poyer already has three pass breakups and an interception, while Hyde has three picks.

The player holding the defense together so far has been rookie cornerback Tre’Davious White. The same innate ability to break up passes that Poyer and Hyde possess is also present in White, except White has the athleticism to hold up on the outside. White’s 12 pass breakups were third in the nation in his last year of college at LSU. He was a perfect fit in Buffalo when it drafted him and somehow looks even better than perfect now. He has already broken up six passes through four games to lead the NFL. White has only allowed 13 completions on 26 targets for 162 yards and a passer rating of 53.8. The 27th overall pick is a star in the making.

Outside of the back end, they have been purely common-sense changes up front. The defensive line has always been talented with Kyle Williams, Jerry Hughes and Marcell Dareus, but in Rex Ryan’s two-gapping 3-4, they didn’t have the freedom to attack. With that scrapped, it’s no surprise those guys are again impact players. While Ryan has shown he’s a great defensive mind, his biggest downfall was trying to force his players to fit his scheme instead of vice versa. With defensive schemes as fluid and malleable as they’ve ever been, finding a way to best deploy talent has never been more important. The Bills are the perfect case study for why.

Mike Renner is a writer for Pro Football Focus and a contributor to The Washington Post’s NFL coverage.

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