Over the course of their careers, Richard Sherman, Earl Thomas, and Kam Chancellor have played in 249 of a possible 252 games, including playoffs. The only blemish being a game missed by Chancellor in 2011 and two more in 2014.

In a sport that's entire design is predicated upon big men hitting other big men, that's a pretty impressive feat.

What the "Legion of Boom" have been able to accomplish over that period of time is nothing short of competitive magic. The trio have combined for nine Pro Bowls, nine All-Pro nods, 55 interceptions, and have helped the Seahawks lead the league in pass defense for each of the last two seasons. Sherman has six more interceptions than any other player since 2010, which is especially impressive considering he was at Stanford in 2010, didn't start until halfway through his rookie season and the ball is rarely thrown in his direction.

There is some debate as to whether or not Sherman is the best corner in the game (he is no worse than top 3) but it's harder to argue that Thomas and Chancellor aren't the best free safety and strong safety that the NFL has at the moment. In the way that people still talk about the Steel Curtain and Purple People Eaters some 50 years later, they will still be talking about the Legion of Boom in 2065, some 49 years after my death.

(Wait, what???)

The fact that these three have almost never missed a game didn't really give us an opportunity to imagine what it would be like without any one of them ... Until now.

Sherman and Thomas appear to be ready for the season opener, but it seems as though the team is prepared to let Chancellor feel out what it's like to miss a game check. I don't expect Kam to miss much more than that, but whether or not he returns in the next week or not, we can now imagine what it is like to have a defense without him. On top of that, Thomas will not play in any of the preseason games, while Sherman will probably have played in about two or three quarters worth of action. Injuries and contract disputes have put Pete Carroll's all-time defense up for a test unlike anything they've faced over the last five years.

And I'll be damned if they aren't passing with flying colors.

The funny thing about those Purple People Eaters that we so often reference here as all-time great units is how most of us overlook that many players involved with it were fungible. Alan Page and Carl Eller were the two guys that were around for most of it, and each made the Hall of Fame, but several other players rotated out for someone else and were bouyed by the play of Page and Eller.

Jim Marshall made the Pro Bowl in '68 and '69, Gary Larsen in '69 and '70 (and was unknowingly doomed for "Did you mean Gary Larson?" search results decades later) but those were the only such nods for those two. They also had Paul Krause, a Hall of Fame safety, and Jeff Siemon, a four-time Pro Bowl middle linebacker. Elite play from a few of your players can raise the play of their teammates to near-elite, or at least, "hella good, son."

Look at the early-2000s Tampa Bay Buccaneers, for example.

Elite play at the front (Warren Sapp), middle (Derrick Brooks), and secondary (Ronde Barber, John Lynch) allowed for several other guys to get recognition they may not have gotten otherwise. Simeon Rice, Shelton Quarles, Dexter Jackson, Donnie Abraham, Anthony McFarland, and others. Perhaps we could even go further and say that Lynch was able to be what he was because of the three other guys, who are even more undeniable.

With Seattle, I feel this is an even more complicated situation. Not only because I've watched these guys grow for five years and because I'm so close to the situation that I may not be able to see the forest through the trees, but due to the fact that I'm having a hard time denying the fact that the defensive line might actually be in a position to overtake the secondary as the most valuable unit on this team.

And that feels like an absolutely gross thing to say. That I'll be lambasted as a delusional homer with no sense of up or down, left or right, back or forward. Which honestly has me questioning my own sanity, like, "Are they right about me? Have I gone a step too far? The crazy don't know they're crazy. Shutter Island was a good movie."

But over these three preseason games, even if they are preseason games, we've been given an opportunity to witness an LOB-less defense and it's been pretty damn good.

All we have is what we have, but this is what we have: Facing first team against first team in PW2, the Seahawks held the Chiefs to seven points in the first half, while Alex Smith was just 11-of-18 for 81 yards, one touchdown and one pick-six interception. They didn't play Jamaal Charles, which is ... significant ... but they did have Jeremy Maclin and Travis Kelce. While Seattle didn't have all three of those LOB guys that are supposed to be the backbone of the defense.

Yet Smith had 4.5 yards per attempt.

In PW3 against the San Diego Chargers, the Seahawks gave up just two field goals in the first half with Philip Rivers going 13-of-19 for 140 yards, no touchdowns or picks. What we have to work with is not perfect, I know this, but in a game-worth of action against first team offenses by KC and SD, Seattle's defense allowed 13 points despite not having their backbone, except for Sherman in a spell versus the Chargers.

I'll take it.

What they relied on instead was something that we've considered to be something of a "weakness" (relatively) these last few years: The defensive line.

Something that I often forget is that Michael Bennett and Cliff Avril didn't arrive until 2013. They were one of the main reasons that Seattle won the Super Bowl, and Avril's injury during Super Bowl 49 was a big reason why they didn't repeat. (Not his fault, but it's true.) But still, nobody had more than seven sacks last season and overall the Seahawks ranked 20th in sacks. Does that matter?

In the context of them being one offensive play away from repeating, no it doesn't, but in terms of reaching the Super Bowl again, it might. So, will Seattle improve their defensive line play in 2015?

Did Daniel-son improve his kick technique?

The Seahawks not only return Michael Bennett (a defensive player of the year candidate on any team where he's not being overshadowed by 10 other guys who are also great at defense) and Avril, but they're adding players through the draft, free agency, and returning from injury.

Brandon Mebane missed seven regular season games and the playoffs and might be the most underrated player on the defense. Jordan Hill, who had 5.5 sacks in 13 games, could be poised to overtake Mebane as the best DT on the team. Ahtyba Rubin was given almost no chance to succeed in Cleveland (a tale as familiar as Cinderella) but has received a lot of praise for his work so far in Seattle.

On the outside they've got Bennett and Avril, but two other players seem like they could be a few months away from degrading any contract leverage that those two players have should any renegotiations take place: Frank Clark and Cassius Marsh.

Clark already looks like he might be one of the best run-stopping defensive ends in the NFL, but given the push we've seen him produce in the preseason, I'll be sufferin' succotash if he doesn't get at least a half-dozen sacks this year. Marsh's productivity last season was hindered by injury, but he also looks like a starter-caliber defensive end through training camp and preseason thus far.

Overall, there are seven players that I think you can be legitimately excited about who are rotating through those four positions ... actually, eight when you consider that Bruce Irvin is a de facto defensive lineman and might be prepping for the best season of his career. I know that facing the LOB can be daunting, but now it seems as though offensive coordinators really have to take the front-"four" into consideration before they can even start to gameplan for how to get past the back-four.

Did I mention that Bobby Wagner is an All-Pro and that K.J. Wright is one of the very best 4-3 outside linebackers in the game?

(I know I didn't mention it, I'm the writer of the article. I was just being cheeky.)

I don't yet know what to make of this defense, just like I don't know what to make of heaven or a quadruple-rainbow. There seems to be so much that it is overwhelming. Maybe it's a "too big to fail" situation and we aren't prepared for the worst because we'v'e come to expect the best, but this much I'm sure of:

Given past performance, current performance, and everything we've come to understand when predicting future performance, the 2015 Seattle Seahawks should have one of the greatest defenses of the modern era. That's because now we can see that they have a lot more than just the Legion of Boom.

The Seahawks had to play without the most important players in order for us to find out that the "important players" ran deeper than we had previously thought.