during their game at Bank of America Stadium on September 8, 2013 in Charlotte, North Carolina. Bobby Wagner (Streeter Lecka/Getty Images)

We’ve all seen the brilliance of the Legion of Boom. Earl Thomas, Kam Chancellor and Richard Sherman may be the very best in the league at their position.

We’ve also seen the havoc wreaked by the likes of Michael Bennett and Cliff Avril from their defensive line spots. In contrast, the Seattle Seahawks’ linebackers have gone relatively unheralded. Not unnoticed, and certainly not under-appreciated by the organization and their own teammates, but they do not receive the kind of accolades players in other units do on a regular basis.

Free agency looming for all three starting linebackers –outside linebackers K.J. Wright and Malcolm Smith after this season, middle linebacker Bobby Wagner after the 2015 season. It’s difficult to argue that all three shouldn’t be brought back for the long haul, but the Seahawks may not be able to keep them all and the general consensus appears to be that Wright is, or at least should be, highest on the list to retain. Smith played terrific football in 2013, en route to a Super Bowl MVP.

Wright’s athleticism has been key in the Hawks’ ability to take out the league’s top tight ends, such as New Orleans Saints star Jimmy Graham and Vernon Davis of the San Francisco 49ers.

There’s a really strong case for Wagner, however, considering he’s the signal caller for the unit and it may be an easier task — and a more effective one — to replace Wright or Smith than find a new middle piece to the linebacker corps, which, of course, also means some level of a learning curve for the new QB of the linebackers.

This question was posed to 1090 The Fan’s NFL analyst and former Pro-Bowl center Robbie Tobeck.

“If you’ve got that quarterback of your defense in a middle linebacker … you think of all the great defenses through the NFL’s history, they’ve all had great middle linebackers, so that guy is tough replace, and I think that’s priority. You want to keep that guy around here.”

Wagner, however, is making any decision a lot easier for the Seahawks’ brass. He’s playing lights out football through three weeks of the 2014 schedule, and his 2013 season may have been better than traditional statistics or even some of the metrics may suggest.

Tackle totals don’t say much, even for middle linebackers. It’s a statistic that does not account for making the right call, being in the right place, staying on assignment or even making a play beyond the player’s assignment without making errors of assignment integrity. It also does not account for missed tackles.

Wagner did, however, finish No. 12 in all of the NFL in total tackles a year ago, and led the league after three weeks this year.

Pro Football Focus studies every player on every play and hands out grades in all areas of responsibility. Last year, Wagner graded out as the No. 12 inside linebacker in football, which is pretty darned good. He ranks No. 2 so far in 2014.

Among the areas Pro Football Focus grades for an inside linebacker include production versus the run, in coverage and on pass rushes, as well as avoiding penalties and missed tackles. They cover it all, and Wagner grades very high.

Let’s take a little step further, thanks to Matt Hamilton of Football Educator. For two years, Hamilton studied linebackers, scrutinizing the tackle statistic. Not just on its value, or lack thereof, but the accuracy of the totals themselves.

Hamilton shared some of the results of his study and began to quantify the difference between one tackle and another. The only metrics available other than the simple tackle is the tackle for loss, or the sack. Hamilton broke it up into five areas:

Tackle resulting in a gain of three yards or fewer and does not result in a first down

Tackle that prevents a third or fourth down conversion

Tackle for loss

A Sack

A tackle that forces a fumble

Hamilton’s findings using the above criterion, as he demonstrated here, reads as follows:

My findings served to add a layer of separation between players that rack up high numbers of tackles and players that make meaningful plays. The most accurate barometer of this was looking at players Impact Tackles per game. I found that the average starter fell around 3.5 Impact Tackles per game, the pro bowl caliber players fell around 4 per game, and the elite players averaged upwards of 4.5.

Hamilton revealed that only three players averaged more than five impact tackles per game over the past two full seasons, 2012 and 2013.

One of them is Wagner.

You can watch Wagner week-in and week-out and the 24-year-old makes it clear how good he truly is, despite being overshadowed in the limelight by Smith, Wright, the team’s sack masters and the elite secondary.

When it comes time to decide which players to keep and which to let walk via free agency, don’t expect the Seahawks to overlook Wagner. If they have to make a decision between Wagner and one of the two outside ‘backers, Wagner is likely to be deemed the most irreplaceable.

He might just be the best of the group, anyway.

– Jason A. Churchill, 1090 The Fan

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