What Legion of Boom? Seahawks' defense is no longer intimidating

The Seahawks’ defense once had the reputation of being one of the most intimidating units in the league. Now, nobody seems to be scared of it anymore. What happened?

For much of the past three-plus seasons, the Seahawks have been viewed, even privately by opponents, as the baddest team on the block. From Michael Bennett, Cliff Avril and the Legion of Boom on defense to the punishing running of Marshawn Lynch, Seattle was built to push you around, especially in the fourth quarter.

Since the Rams came back from a 27–10 deficit with 8:47 remaining to in 2004, the Seahawks were 49–0 when they held a double-digit fourth-quarter lead.

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And then, Super Bowl XLIX arrived, and Tom Brady happened. And now, no one seems to be afraid of the Seahawks.

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If the officials didn’t err by not calling illegal batting on linebacker K.J. Wright against the Lions in Week 4, the Seahawks would be staring at blowing fourth-quarter leads in five of their past six games (a 26–0 victory over the Bears in Week 3 the lone outlier), including three by double digits (to the Patriots, Lions and on Sunday the Bengals). The Seahawks are 25th in the league in scoring defense in the fourth quarter (8.4 per game). The previous three years, they were among the league’s best: 3.9 in 2012 (second in the league), 4.2 in ’13 (third) and 4.4 in ’14 (fourth).

What’s going on? Not even Pete Carroll knows.

“I’m baffled a little bit,” he said Sunday, after his team led 24–7 in the fourth quarter and lost 27–24 in overtime. “We’re very clear about what we want to do and how to get it done. What’s startling is that it’s not happening. We’ve had to be terrific in this mode for years to be able to do what we’ve done. The last three games have been the same story line at the end. If we can fix that, we can change the season and that’s what we plan to do.”

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He can start on defense, where the Legion of Boom has given way to the Legion of Bust. The numbers are so startling they don’t seem real. But they are.

From 2012 through ’14, when Seattle was dominating on defense, opponents completed 60.1% of their passes, had a 14–22 touchdown-to-interception ratio and posted a quarterback rating of 69.3 in the fourth quarter.

Starting with Brady’s march to immortality, Seahawks opponents have completed 86.0% of their passes and posted a 135.5 rating in the fourth quarter of six games. Seattle also hasn’t intercepted a pass.

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Certainly there isn’t just one reason why a team keeps blowing fourth-quarter leads. And the Seahawks’ offense, which runs in spurts even when it’s going well, hasn’t been a big help. But the passing and rushing hasn’t really gone downhill. From 2012 to ’14, quarterback Russell Wilson completed 61.3% of his passes and posted a 99.5 rating. In the past six games, he’s completed 59.6% with a 68.1 rating. Wilson’s interception percentage (2.7 to 2.6) is about the same. However, there’s been a huge change in his touchdown percentage (7.4 to 2.6). That drop and the one in his rating could actually be attributed to the defense: It’s not stopping anyone, so the field position difference is costing the team points.

The team’s fourth-quarter rushing is actually better. From 2012 to ’15, the Seahawks averaged 4.17 yards per rush in the fourth quarter. In the past six games they have averaged 4.26.

Numbers can’t tell everything, especially when you’re comparing a 48-game sample to just six games. And there indeed may be nuances in those six games that point to a larger reason why the Seahawks can’t put anybody away. The struggles are probably also influenced by the fact that four of the teams the Seahawks have allowed back into games (the Patriots, Packers, Lions and Bengals) can function at a high rate when they need to.

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But it’s hard not to look at opponents’ fourth quarter 86.0% completion percentage and 135.5 rating and not put the Seahawks’ defense at the top of the list of places to place blame. When an opponent is having that easy of a time completing throws, something’s broken and we can now say with near certainty that safety Kam Chancellor, who held out the first two games this season, is no cure-all for that unit. He was on the field when Brady hit on 13 of 15 passes for 124 yards and two touchdowns down the stretch in Super Bowl XLIX (140.7 rating), when Matthew Stafford connected on 8 of 8 fourth-quarter passes for 80 yards (108.3 rating), and when Andy Dalton led four scoring drives in the fourth quarter and overtime in Week 5 by completing 13 of 15 passes for 135 yards and one touchdown (126.4 rating).

When things are going that poorly, it’s usually the entire unit, and pass defense is a marriage of pass rush and coverage, so neither is getting it done well enough. Personnel in the secondary could also be an issue, even aside from Chancellor’s missed time. ​After disappointing in Philadelphia, ​cornerback Cary Williams (allowing a 115.0 opponent passer rating, according to ProFootballFocus.com) was signed to step in for free-agent departure and current Eagle Byron Maxwell (81.1 last season). And in the slot, Marcus Burley (91.7 rating) and DeShawn Shead (86.6) have not replaced Jeremy Lane (78.0), who suffered a torn ACL and wrist fracture on the first play of Super Bowl XLIX.

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New England also seems to have given the Seahawks’ opponents a blueprint for moving the ball against them. The Patriots didn’t even try to pass vertically against Seattle; they spread the defense out and used quickness on short crossing routes and checkdowns to the backs to keep the Seahawks on the field, wear them down and take advantage of matchups.

Whatever the problem is, and it’s likely a little bit of this and that, the Seahawks have to find a way to correct their pass defense in the fourth quarter. Right now it’s a sieve, and the season is sliding through it.