A generation ago, nike nfl defense was about aggressive coverage, beating your man at the line, and relatively simple “if this/then that” pattern-read concepts. As much as the league’s great defenses are always about talent, they’re more about scheme than ever before these days. In the truly modern NFL, defenses substitute entire positional rotations, play nickel and dime defense at least half the time, and must counter offenses looking to stretch the field in ways we’ve never seen. Add a dizzying array of option routes, more and more option quarterbacks who can actually throw the ball, and a new emphasis on speed no-huddle sets, and it’s clear that the task of providing premium nfl shop defense on a week-to-week basis (never mind season-to-season) is tougher than it has ever been before.

Thus, the onus is on general managers, head coaches, and defensive coordinators to not only find the best players, but to specify and scout those players who are best for their systems. More defensive players are specialists these days — nickel corners, rush ends, linemen for heavy packages, and half-field defenders masquerading as linebackers.

NFL shirtsteams capable of putting great defenses on the field should be credited more than ever for doing so, because it’s a post-graduate course these days. Based on prior performance and off-season addition and subtraction, here are the five defenses we believe will provide the most headaches to opposing offenses in 2013.