Legion of Boom is a 10-year-old hit album by techno band The Crystal Method.

THE Legion of Boom is the brazen, hard-hitting, trash talking secondary of the NFC champion Seattle Seahawks -- and one of the great statistical storylines of the 2013 season. 

Leading Legionnaire Richard Sherman displayed the best and worst of the unit in the final seconds of Seattle’s 23-17 win over the San Francisco 49ers Sunday night in the NFC championship game.

Good Sherman tipped Colin Kaepernick’s final pass in the end zone, deflecting it to teammate Malcolm Smith for the INT. The play against receiver Michael Crabtree, one of the most physically gifted and dangerous receivers in football, preserved Seattle’s victory with seconds to play.

Bad Sherman then appeared unhinged and ungracious in the post-game interview with Fox Sports reporter Erin Andrews.

“I’m the best corner in the game!” boomed Sherman, practically spitting all over the poor, shocked reporter.

“When you try me with a sorry receiver like Crabtree, that’s the kind of results you going to get. Don’t you ever talk about me!!” – a reference, apparently to some words he had with Crabtree during the game.

Regardless of the outburst, the result confirmed the statistically powerful profile of the Legion of Boom and the entire Seattle defense.  

This unit powered the Seahawks all season long, as the team dominated the NFL in the most important skill any defense can have: making life miserable for opposing quarterbacks. The 2013 Seahawks finished the year:

Just for good measure, that defense was also No. 1 on the Defensive Hog Index, No. 1 in Defensive Rusher Rating and No. 1 in Total Team Yards Allowed.  

The Legion of Boom flexed all those statistical muscles in the NFC title game, especially in the fourth quarter, launching Seattle and its top-rated pass defense into an epic Super Bowl XLVIII showdown with Peyton Manning, the record-setting Denver Broncos and the top-rated pass offense this season.


Colin Kaepernick and the 49ers falter in the fourth

San Francisco's exciting and athletic young quarterback ran almost with impunity, racing around the Seattle defense 11 times for 130 yards.

But the far more important passing performance just never quite materialized, a problem that has plagued Kaepernicks’ game since Day 1, despite all the accolades. The final numbers against Seattle Sunday:

  • 14 of 24, 58.3%, 153 yards, 6.4 YPA, 1 TD, 2 INT, 56.4 rating

The performance Sunday mirrored almost perfectly the pedestrian numbers we’ve come to expect from Kaepernick against the Seahawks in four games:

  • 61 of 117, 52.1%, 699, 6.0 YPA, 3 TD, 7 INT, 54.0 rating

Kaepernick’s two picks came in the fourth quarter, as did his lone lost fumble. In fact, with the game very much winnable for the 49ers, Kaepernick coughed up turnovers in each of his team’s final three drives.

He was simply no match for the Legion of Boom. Of course, few quarterbacks have been this season.

But to his credit, Kaepernick manned up straight away in the postgame press conference.

“I turned the ball over three times. I cost us this game,” said Kaepernick.

It was a primer in QB responsibility that should be taught to every Andy Dalton in the NFL.


Russell Wilson’s Rough Start, Big Finish

Seattle’s own bright young quarterback produced something of the anti-Kaepernick performance on Sunday.

And that performance proved critical.

He was sacked and fumbled on the first snap of the game, helping hand San Francisco an early 3-0 lead.

He ran ineffectively (2 for 3 yards, followed by three kneel downs to end the game, which count as carries for -1 yard each).

But Wilson excelled against the dangerous San Francisco defense in the one area that makes him the best young quarterback in the game – bar none – yet for which he gets little to no credit.

Wilson was a deadly efficient game manager – the single best thing you can say about any quarterback.  

His final passing numbers:

  • 16 of 25, 64.0%, 215 yards, 8.6 YPA, 1 TD, 0 INT, 104.6 rating

They are gorgeous, pristine numbers for anyone who values winning football: solid completion percentage, high average per attempt, zero INTs and highly effective passer rating.

The lone touchdown pass was a beauty: on a free play on which the San Francisco defense was caught offsides, he threaded a 35-yard TD pass into the hands of wide receiver Jermaine Kearse. It gave Seattle a 20-17 lead, its first of the game, in the early moments of the fourth quarter.

It was just about what we’ve seen out of Wilson all year: he and the Seahawks finished No. 5 this season in Offensive Passer Rating (102.4).

Those numbers spell victory almost every time, especially when your rating nearly doubles up your opponents (104.6 to 56.4, a Passer Rating Differential of +48.2 on the NFC title game).

And there then, lies the simple secret to the dominance of the Seattle Seahawks in 2013 and their victory Sunday in the NFC title game: Wilson is beautifully efficient and opposing quarterbacks are rendered ugly and inefficient by the Legion of Boom.

Seattle finished the season No. 1 by a wide margin in Passer Rating Differential (+38.97). It’s a great sign for the Seahawks as they attempt to capture the first Super Bowl victory in franchise history.

As we’ve often noted, 26 of the 73 NFL champions since 1940 (36%) finished No. 1 in Passer Rating Differential – the reason we call it the Mother of All Stats.

But Peyton Manning and the Broncos will be no pushover: they finished the year No. 2 in PRD, and No. 1 with a bullet in Offensive Passer Rating.

So Super Bowl XLVIII offers us a statistically perfect Super Bowl: the two teams that dominated the skies over NFL battlefields better than any others this year. Denver led by the amazing Manning and the most efficient passing attack in football, Seattle led by quiet young star Wilson and the brash, loud-mouthed Legion of Boom that has silenced opposing quarterbacks all year long.