It’s difficult to discuss the “best all time” anything in the NFL, because the game changes so much and so rapidly. I suppose that’s true to some degree of any sport, but the intricate parts of the football machine move so much quicker, with schemes on both sides of the ball rarely staying stagnant from year-to-year. Say, remember the Wildcat? That was fun for a year or so, and now we have the read-option, a system defensive coordinators studied all last offseason.

The endless battle between the X’s and O’s is an ever-morphing cycle, which is why saying “this team is the best EVER at this” is difficult, because times and circumstances change.

Consider that preamble my disclaimer. Now, let’s get on with the reason why we’re all here: to wonder if while we watch the Seattle Seahawks play defense this Sunday and maybe again two weeks from now, we’re watching one of the best pass defenses of all time. And if so, how have they come to claim that title?

The answer to the first question is a resounding “yup”, though they’re not THE best. That title still belongs to the 2002 Tampa Bay Buccaneers, which is the conclusion Chase Stuart came to last week after doing his best to account for the variances in the different eras using advanced analytics (also known as fancy stats). But the Seahawks are right behind them, with the second best pass defense since 1970.

One particularly daunting number is the Seahawks’ adjusted net yards per attempt (ANY/A), an upgrade over team passing yards allowed because it’s a metric that doesn’t include sacks and plays with lost yardage, and it therefore focusses only on plays when the ball is in the air traveling forward. The Seahawks allowed just 3.19 adjusted net yards this season, according to Stuart, which is 1.20 better than any other defense.

That’s frightening, as are two first-team All-Pros in the Seahawks’ secondary between Richard Sherman and Earl Thomas, with Kam Chancellor getting some second team dap. The fright grows when we focus on this era, one which has had plenty of passing. I’m not sure if you’ve noticed that, or if you’ve heard about such an era at least once every Sunday. But we’re definitely in the middle of it, and there’s no better gauge of the passing volume than this…

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Compared to this…

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We’re not there yet, but thanks to recent rules changes aiming to protect quarterbacks and defenseless receivers, we’ll laugh at our former selves when we considered a +5,000 yard season to be Herculean. You may be laughing at me right now, but look at those leaderboards again, and note that Dan Marino’s original single-season passing yards record stood for 26 years, and his mark has now been broken five times since 2011, most recently by Peyton Manning this season. A 5,000-yard passing year will always be significant (I think), but it could quickly become far less heroic.

That shows how difficult it is for the Seahawks to be doing what they’re doing as they prepare to host the San Francisco 49ers this Sunday. Yet here they are, one win away from the Super Bowl after a season when they allowed only 172.0 passing yards per game, while also leading the league in interceptions (28), yards allowed per attempt (5.8), interceptions (28), and opposing passer rating (63.4). This is a defense that’s just the fourth in league history to rank No. 1 in both interceptions and yards allowed.

How have they achieved this madness?

Richard Sherman is an animal

I’m not exactly sure what kind of animal Richard Sherman would be. But if I had to guess, I’d say a capybara due to how easily they annoy you with that “pew pew pew pew” sound or whatever.

I’m endlessly fascinated with this Sherman stat. According to Pro Football Focus, he was the least targeted cornerback with only 58 balls thrown his way throughout the regular season, and yet he still led the league with eight interceptions, and recorded 24 passes defensed. That math also leads to this: Sherman intercepted 13.8 percent of the passes thrown his way.

Naturally, Sherman spent most of his time lined up across from the opposition’s top receiver, and looking back at the results of that setup is pretty comical. Through the season’s 16 games, the opposition’s leading receiver averaged 69.6 yards. Cecil Shorts (143 yards) and T.Y. Hilton (140 yards) were the only two who went off, and the former did it during garbage time of a 45-17 Seahawks win.

Predictably, the passing yards allowed by Sherman et al tumbled further at CenturyLink Field, dropping to only 154.4 yards per game. That’s daunting for Colin Kaepernick this weekend, who was held to just 127 yards on 4.5 per attempt back in Week 2, a game when he threw three interceptions, fumbled once, and finished with a passer rating of only 20.1.

A system predicated on Pressure

Sherman is certainly great on his own, as are Thomas, Chancellor, and Byron Maxwell, who’s playing for the suspended Brandon Browner and has fared far better than the guy he replaced, with four interceptions over just the final four weeks of the season. But they’re all often able to cheat and remain menacingly aggressive because Seattle’s defensive backfield knows opposing quarterbacks simply don’t have that much time.

At it’s foundation, their pass defense is rooted in not letting the pass leave towards a desired destination at all. The Seahawks are absolutely stacked up front, and became even more so last offseason when both Michael Bennett and Cliff Avril were brought aboard. With Red Bryant, Chris Clemons, and pass rush specialist Bruce Irvin (who led all rookies last year with eight sacks) also firing off the edges, they’re so loaded that Bennett has often moved inside this year, playing 340 snaps as a rush end, and shuffling to the interior for 333 snaps, according to Pro Football Focus.

When Bennett is inside and Irvin stands up at outside linebacker on a passing down, the Seahawks then have four natural defensive ends rushing the passer. That’s how their pressure was so widespread while coming from a variety of looks and angles. Seattle finished the season with 44 sacks, and Avril led the way with a solid but modest 8.5.

Pass rushing is about more than sacks, of course. Pressure forces mistakes and balls thrown prematurely, and to get that result with the quarterback still standing, a rush needs to be consistently brutish. That’s what Bennett did.

Bennett was on the field for 379 pass rush situations, according to PFF, and he pressured the quarterback on 13.5 percent of those snaps, the seventh best rate in the league. Bennett also had 51 quarterback hits (fifth).


This Sunday when Kaepernick goes to a place where his two starts have ended in a combined score of 71-16, passing will remain somewhere between difficult and impossible. Running isn’t necessarily easy, but it’s easier, especially with K.J. Wright likely still out, though he has a chance to play.

We’ll should see plenty of the ageless and still quite wonderful Frank Gore then, whose matchup isn’t nearly as daunting as it may seem.

Wright’s potentially still lingering absence also means pleasant things for Vernon Davis, as the linebacker was key in a Jimmy Graham shutdown earlier this season, holding a tight end who averaged 75.9 yards per game to 42 yards in Week 13, though he scored. A week later in the game when Wright broke a bone in his foot, Davis was limited to only two catches for 21 yards (though he also scored).

Hope for the 49ers and any passing aspirations they have also comes in the form of Michael Crabtree, who missed the first meeting between these two teams back in September because of his Achilles injury, and then still wasn’t quite himself yet in Week 14. As the layers of rust have gradually been discarded, Crabtree has returned to being Kaepernick’s high-volume target, giving him a chance to create after the catch. Over two playoff games Crabtree has been targeted 20 times, and a week ago against the Packers Kaepernick was particularly focused on him, as he was the target on nearly half of the quarterback’s pass attempts (13 of 30).

On a fundamental level against this imposing Seahawks secondary supported by imposing pass rushers, those three — Gore, Davis, and Crabtree — should be featured prominently. Pounding will happen on the ground, and then yardage will be accumulated patiently through high percentage, short throws. Maybe.

Recent history tells us attempts to deep ball will be futile against this secondary in Seattle, one that allowed the fewest receptions for 20 yards or more throughout the regular season (30). In Week 2, the 49ers’ top receiver was Kyle Williams with only 39 yards, while Sherman blanketed Anquan Boldlin, holding him to only seven yards on one catch.

There will be noise Sunday, and there will be helmet mashing. But passing? Likely not so much.