The Seahawks' D versus the Broncos' O is mostly a matchup of strength on strength. A HoF QB and his great WRs matching up against one of the best secondaries in NFL history. A very strong and ferocious defensive line against a relatively weak offensive line, but one that is compensated by a quarterback with great pocket presence and ability to get rid of the ball on time (#1 in adjusted sack rate, where #32 is the Seahawks, showing again how much sack rate is a quarterback stat).

The matchup that makes me nervous more than any is the Broncos short passing game against the Seahawks linebackers (and Kam Chancellor, Deathbacker).

So let's talk linebackers, starting with Bruce Irvin. Despite all appearances, Irvin has not had a bad year for the Hawks. I was skeptical of the "move a Leo to linebacker" talk in the offseason, mostly because I couldn't see it happen with Chris Clemons or Cliff Avril. Bruce though? Bruce is a really odd kind of hybrid player, because somehow he has a hybrid skillset of a pass-rusher and a defensive back. That is pretty unique.

When he was converted to linebacker I expected him to be an exciting player who would make some really flashy big plays but also whiff majorly on others, and I suppose that's what everyone expected and would have been happy with.

Instead, to my pleasant surprise, we got a linebacker who has been very quickly trained-up to play careful, assignment-correct football. A player who plays with patience and avoids mistakes, which comes at the cost of flashy big plays. This has made him largely invisible, as the strong-side Sam enforcer his main job is to keep his side sealed, which has lead to the conclusion that he had a bad year. He did not, for a first-year convert this kind of reliability is excellent, and he should be able to combine the lessons he learned with his athleticism to break out big next year.

He's not a difference-maker yet, but he's showing that physical skillset that warrants the Von Miller comparison, and I'm excited about where he's heading.

Witness these GIFs, where Irvin has no other job than to spy on Kaepernick (which was the crux of our second-half adjustment; rush hard from defensive left, put Irvin in to spy from defensive middle/right). Not a glorious job, but a very difficult one to execute correctly, and one that shows the trust Quinn has in Irvin to remain assignment-correct. With his combination of patient play and ability to burst into game-changing plays, I have dubbed him The Patient Assassin.

That said, Irvin's not a major part of the defense right now, and even though he is a "starter," he is playing sub-50% of snaps both of the playoff games

(Aside: when will we finally change the "starter" designation from "guy who played first snap of the game" to "guy who played majority of snaps of the game?").

Bobby Wagner played every defensive down this post-season, and he is the taskmaster at one of the most difficult parts of defending a Manning-led offense: keeping a lid on the run. Manning-led offenses have always been one of the easiest for running backs to operate in, because Manning is nearly flawless in switching to a run when he spots the defense overselling to stop the pass.

Since the Broncos mostly play single-back and thus always overload you with pass-catching options, it is not really an option to stay in vanilla to prevent these audibles. Instead, you have to rely on your front-seven to stay picture-perfect in gap containment, and to wrap up their tackles.

If this makes the hairs on your arms stand up you're not alone, because this is describing something the Hawks have struggled with in several games in in consecutive seasons. It's not currently a problem, but that doesn't mean the potential pitfalls are there; the problems with gap discipline and over-eagerly diving into gaps, and issues with wrapping up tackles, are not affordable errors in this game. If they do, each Knowshon Moreno run turns from a small gain (it is practically impossible to turn these audible runs into losses) to major gains for easy first downs, which would simplify the game for the Broncos in an unacceptable way.

That said, the defensive line's run-stopping prowess has been nothing short of amazing this offseason, with Brandon Mebane being one of the better players on the defense, consistently collapsing the pocket and occupying two linemen. Mebane and Red Bryant will limit the freedom of these runs, which makes Wagner's job as the primary run-stop guy easier. And if he doesn't make it, Kam Chancellor will be there to clean up what he misses. Tackles are not generally a useful stat, but their combined tackle stats for the post-season (24 and 25 respectively) speak clearly to their roles and reliability not just in containing the run, but also in smacking the living daylights out of anyone who dares venture in their territory.

What's more, KJ Wright is coming back, and this to my mind is one of the bigger game-changers. When KJ Wright went out for a few weeks, I argued it would not make much difference to the defense, because 4-3 LBs are rarely that valuable.

Indeed, our defense did not skip a beat, but my assertion also had a lot to do with which teams we were playing in this period. From these games (@NYG, ARI, STL, NO and partially SF), NO was the only game where I feared missing him would have a major effect. If you'll remember, this is what KJ Wright did when we played NO in W13:

We found different solutions for Jimmy Graham thankfully, but this illustrates what makes me consider KJ Wright the best of our linebacking set. Where Irvin is still a little raw and Wagner has somewhat of a tendency to misread passing plays, Wright is solidly reliable in the type of plays where you'd rarely want to depend on a linebacker, or would feel you're in a disadvantage on that matchup. That's not to say he's flawless or the equal of a defensive back, but he has outstanding skills in coverage and play-reading for a linebacker.

Whether it is perfectly sniffing out a screen pass or single-cover a top-shelf tight end, Wright is the one linebacker of our group that actually significantly impacts the opposing team's gameplan, and while it is unlikely to have the impact Harvin's return does, we should not undersell how important it could end up being to have him back for exactly this matchup, one which significantly challenges the discipline and play-reading ability of our linebackers, as well as their physical ability to match up with a top-level tight end.

If there's one thing this defense delights in doing, it's defying the ability of casual viewers to easily identify a player's position. It is pretty much impossible on our defensive line, which shuffles people around like nobody's business, but there's another quandary wandering around in the box in Kam Chancellor, our Deathbacker.

While a part of the Legion of Boom - heck, arguably the part that truly justifies the Boom part of that name - the Deathbacker spends a significant portion of his snaps playing what is essentially a linebackers' role, cleaning up pass-catches by TEs and RBs, or stopping the run. His skillset allows for more than this, but his ability to play the roaming Deathbacker so well is what allows us to keep enough people in the box even in nickel sets, putting Bruce Irvin on the sideline.

Now, I just argued Bruce is playing fine, so why would that be a good thing? Because we'll likely have to lean on the outstanding abilities of our CB depth, whether it is Walter Thurmond or Jeremy Lane, both of whom have the flexibility to cover, pass-rush or run-stop enough for us to use the nickel almost as a base formation against this offense, which may be needed considering the receiver-heavy sets.

It sounds like I have nothing but praise and mostly I do, but it does need to be noted that while they are a good group, the linebacking group is probably the weak link in this defense. That is just not saying much because of the incredibly high level this defense plays at. There's gotta be a weak link, even if it's "only good". But this weak link is about to face what will probably be its steepest challenge for this game.

Even with Manning's arm strength recovering somewhat, he still has one of the weakest arms in the NFL right now, and he's not going to challenge our defense's best player Earl Thomas deep down the field, because he knows Earl can simple outrun any deep ball thrown by him. Richard Sherman and Byron Maxwell both match up well with the outside WRs, and while they will be tested and some big plays will happen in those matchups either way, it feels like the shape of this game on defense will be determined by the ability of this defense to contain both the run-game and the short passing game, controlling the flats (and the short area in general). The pass-rush is going to be ferocious either way, but its ability to get home and gain any ground on containing Manning will depend on how well we do in the four zones behind them in our Cover-3 looks.

Playing as they have been for the past two games, and with KJ Wright back at full speed, I feel pretty confident our linebackers (Deathbacker included) are up to the challenge, which doesn't mean they won't allow any short gains. The Pete Carroll defense is built to lure offenses into taking the most attractive option, which is to try and dink and dunk downfield, eventually holding on a third down or forcing a turnover by forcing a fumble or picking off a pass. And make them pay them for every reception they do make.

That's the ideal way for it to go, but for it to work, for us not to be effectively dink-and-dunked to death again this great offense, we are asking this group to be at the absolute top of their game. Anything less and we're likely going to be in trouble.

EDIT: the other matchup I was fascinated by for this game is our offensive line's run-blocking ability (great for most of the season but showing some problems with our ever-rotating offensive line the last half-dozen games) against the Jack Del Rio defense.

Luckily our own Travis Williams did a great job higlighting their defense. I have a great respect for Jack Del Rio's capabilities as a defensive coordinator and I think he got much more out of that defense than the talent level warranted after losing Von Miller (suspension, ACL) and Elvis Dumervil (fax machine). They lack talent on the back end, but JDR has gotten much more out of some of his front 7 players like Terrance Knighton or Malik Jackson than other coaches would.

Like us, he runs an aggressive front seven and while his defense doesn't do a lot of crazy exciting stuff right now, he is one of the top coaches in instilling his players with perfect discipline and tackling form. It is exactly that which makes it so hard to run on this defense, and it'll be fascinating to see how our offensive line (particularly on the interior) and Michael Robinson/Marshawn Lynch fare against them.

This is your classic strength on strength matchup and should be a great one either way.