The past two years, the best defense in pro football has resided in the NFC West. That will be true again in 2015, only this time it won’t be the Seahawks’ D. It will be the team that beat the Seahawks in the Edwards Jones Dome last season. The Rams have won just 13 games during Seattle’s two years of dominance, but they’ve been a team full of young players who are now ascending into the early parts of their primes. The average age of a Rams’ starting defender is 25; the average level of athleticism is “somewhere off the charts.”

Let’s start with the area fans are most familiar with: the defensive line. It features the game’s most explosive edge rusher, Robert Quinn, and, already, the game’s most explosive interior gap-shooter, Aaron Donald, last year’s 13th overall pick. Donald has extremely quick get-off, well-honed footwork and the capacity to shed blocks and redirect in traffic. Though he’s at his best fighting the run, he’s capable of also being a 10-sack pass rusher (rare for a defensive tackle).

Head coach Jeff Fisher and general manager Les Snead have done a great job building the rest of this D-line. In their first year here, 2012, they drafted Michael Brockers in the first round. He’s turned out to be an outstanding pass rushing setup man in sub-packages and a tough one-on-one block on base downs. Fisher and Snead also locked up Chris Long to a long-term deal their first year, which has paid dividends, and they signed former Titan William Hayes to provide depth. And the one remaining player they inherited, Eugene Sims, has blossomed into a productive, versatile backup, capable of starting for many 4-3 teams. (He may get that opportunity next year; Sims is in the final year of his contract. Long’s 2016 cap number is $14.25 million, which the club is unlikely to keep on the books, and Hayes is in the final year of his deal. There will be a hole to fill at defensive end.)

Sims can also play defensive tackle, though with Fisher and Snead snagging free agent Nick Fairley this past offseason, there won’t be as many snaps available there. Fairley’s reliability is questionable—why else would such a gifted 27-year-old garner only a one-year, $5 million deal in free agency?—but when he’s right, he’s similar to Brockers, only with more natural leverage and a little better initial quickness.

Rams linebacker James Laurinaitis. (Photo: David E. Klutho/Sports Illustrated/The MMQB)

At the linebacker level, James Laurinaitis is an intelligent point man whose pre-snap adjustments, blitzes and disguises give this defense diversity. But the headliner of this group will be Alec Ogletree, the 2013 first-round pick who last season began consistently playing up to his considerable level of raw talent. Ogletree, a safety at Georgia, covers ground in the flats and maneuvers well through traffic. He can match up to running backs or tight ends in man coverage, and he’s developing a keener sense for angles as a zone defender. Opposite him is a lesser but still commendable athlete in newcomer Akeem Ayers. He replaces Jo-Lonn Dunbar, who is one of the game’s best at taking on lead-blockers but is an otherwise limited player.

Ayers, a former Titan-turned-Patriot last season, has a multifaceted skillset that has never been fully showcased in his four-year career. There’s no guarantee it will in St. Louis, either. Defensive coordinator Gregg Williams loves employing various nickel and dime sub-packages (more on that in a moment), and he has a great box safety to use in Mark Barron. With Ogletree too good to take off the field and Laurinaitis too smart, Ayers would be the odd man out if Williams again wants to feature Barron’s blitzing in “big nickel,” much like he did after the Rams acquired him from Tampa Bay last October.

Barron won’t start because the Rams already have a potential top-three strong safety in T.J. McDonald. You haven’t heard much about the third-year pro, but that will change. At 6’2”, 220, McDonald covers ground like an antelope when filling down in the box, and he’s an assertive presence in coverage, including man-to-man. At free safety, Rodney McLeod is not Earl Thomas, but he’s fast in his own right, which, with continuously improving awareness, gives him range. McLeod’s growth only affords Williams more freedom for deploying his blitzers.

That’s something Williams does with relentless aggression and creativity. It’s long been his M.O., and, given that he’s built a pressure-based scheme despite having the league’s most dangerous four-man front, it’s safe to declare that it will forever be his M.O. This youthful defense, especially the secondary, had a difficult time initially picking up the nuances of Williams’s system. Far too often, its coverage concepts did not sync up to the design up front.

But this issue abated as last season progressed. Now, with the secondary having just completed a second offseason under Williams, it should all but vanish. Corners Janoris Jenkins, Trumaine Johnson and E.J. Gaines (a surprisingly sturdy presence in the slot as a sixth-round rookie last year who hopefully will overcome a foot injury he’s currently battling) will be asked to play a variety of matchup-zone concepts. Thanks to the pressure designs, each individual will often be able to extend more aggression to his preferred style of play. For Jenkins, this means jumping routes from off-coverage. For Johnson, it means probably the same, he plays a lot of off-coverage on the outside. Gaines, though an inside player, would likely elect to play with more physicality. It’s the strength that has propelled him ahead of fellow rookie Lamarcus Joyner (a second round pick) for slot duties. Gaines is also versatile in zone concepts, which Williams takes full advantage of. (A few times last season, the cornerback even rotated to middle linebacker in Tampa 2 coverage, taking away the deep middle hole in pass defense.)

St. Louis’s defense may not finish first in yards or points allowed this season—though it’s sure to be much higher than near the middle, where it finished a year ago. But in terms of creating team-wide success that contributes directly to victories, it will surpass Seattle as the league’s best D. The Rams’ foundation is built on big plays, and there will be enough of them to put this team in the playoffs for the first time since 2004.

Rams Nickel Package

1. The trade for Nick Foles is another example of the Rams digging in and becoming a totally defense-oriented team. Foles, with his slower delivery and need for clearer defined reads, is built to be a classic game-managing QB. (No shame in that.) This not only fits a run-based offense, it also means the Rams don’t have to sacrifice an enormous chunk of cap space after signing the 26-year-old to a two-year, $24.5 million deal. That leaves more money available for holding onto defenders like Quinn (already signed long-term), Donald, Ogletree and McDonald, all young “top three” players at their positions. This, by the way, is similar to Seattle’s current blueprint, which is why the Russell Wilson contract situation is so interesting.

2. A passing-based offense needs only an adequate O-line. A run-based offense, however, needs a dominant one. Hence the selection of Greg Robinson with the No. 2 overall pick in 2014. Now the fulltime left tackle, Robinson will be the fulcrum of many man-blocking concepts on the perimeter, where his uncommon combination of size and mobility can be highlighted. In the zone game, which new offensive coordinator Frank Cignetti reportedly plans to employ more of this season, Robinson can be a downfield mauler at the point of attack. (Remember, not all zone ground games are laterally based like what we’ve seen from Alex Gibbs style systems over the years. There’s also “inside zone,” which is built on power and double teams.) It was good to see the Rams commit second-and third-round picks to right tackle Rob Havenstein and guard Jamon Brown. Upgrades were needed along the O-line.

3. It’s important that Cignetti help his receivers schematically the way previous coordinator Brian Schottenheimer did. Schottenheimer got production out of middle-tier players like Kenny Britt, Jared Cook and Tavon Austin via stack-release concepts and intertwined route combinations. These tactics also help define reads for the quarterback. Cignetti will have to maintain this because none of St. Louis’s receivers, except for maybe Brian Quick, who missed much of the offseason with a shoulder injury, are capable of consistently creating their own separation.

4. Speaking of Austin, if he’s not featured as a misdirection weapon or decoy at least six times a game, it means the Rams are using him wrong.

5. Two underrated but highly important members of this offense: tight end Lance Kendricks and H-back Cory Harkey. Both are flex pieces behind the line of scrimmage, bringing valuable dimension to the ground game.

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