Seahawks' ability to load up against the run

The San Francisco 49ers appear highly likely to grab the No. 2 seed in the NFC playoffs. They're leading the St. Louis Rams, 20-10, and driving late in the third quarter.

Looking ahead to the late NFC West game between Seattle and Arizona, I wanted to take a closer look at something Gus Bradley, the Seahawks' defensive coordinator, told reporters late in the week.

Bradley was lauding the Seahawks' corners, Richard Sherman and Brandon Browner, when he said their abilities in man coverage give the coaching staff greater flexibility.

"With the amount of eight-man fronts we're playing, it's a credit to the corners because you shouldn’t be able to get away with probably as much as we're doing," Bradley said.

I've put together a couple charts to illustrate when the Seahawks use eight-man fronts and when it matters. Counting defenders in the box area can give us a general feel for how a team plays defense. However, playing with eight-plus defenders in the box reveals less if the opposing offense has additional blockers available. For example, teams will naturally use eight-plus defenders more frequently against San Francisco because the 49ers use fullbacks and tight ends in greater quantities than other teams do.

In general, though, the Seahawks have used eight-man fronts more frequently in recent games. They have also used more "loaded" fronts -- those with more defenders in the box than the offense has blockers available -- over the same stretch.

The first chart shows an opponent-by-opponent look at how frequently the Seahawks have used loaded fronts this season. Sometimes, they have loaded up against teams with strong running games (Atlanta). Other times, they have loaded up against teams with limited passing games (Chicago), figuring they could get away with fewer players in coverage.

In reading their stats against Arizona, remember that the Cardinals were without Beanie Wells when the teams played in Week 3. Wells has carried against loaded fronts only 18 times in 260 rushes, however. They have used eight-man front against him 41 times.

The numbers come from Hank Gargiulo of ESPN Stats & Information.

2011 Seahawks Defense: Box Defenders Outnumber Blockers

The second chart shows an opponent-by-opponent look at how frequently the Seahawks have used eight or more defenders in the box, regardless of how many blockers were available to their opponents. This is where the 49ers' run-oriented offense and preference for heavier personnel groupings come into clearer focus. I was a little surprised to see the numbers so low against Baltimore.

2011 Seahawks Defense: Box Counts