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49ers Defensive Personnel: Perfect fit for 4-3 "under" scheme?

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Ever since the drafting of the versatile Aldon Smith, I've been racking my brain thinking of how the 49ers would get the most out of him on all three downs.  It might seem simple to some: just use him as a DE in Nickel (pass-rusher) and let him slowly learn the other nuances of a complete 3-4 OLB in the meantime.

Let me give you a quick take on Smith and why it isn't to simple to me:

Smith predominantly played DE in Missouri's 4-3 defense, but he also lined up at DT quite frequently as well.  He's a pass rusher first and foremost, a skill I don't want to waste on ANY down.  He's shown the ability to beat guards AND tackles 1-on-1 as well as contain the run to his side AND pursue on runs to the backside.

Simply put: he's a great DE prospect.

But the 49ers selected him 7th overall and we don't run a 4-3 defense (where a DE would line up in the same spot each down and primarily just play the run or rush the passer).  True 3-4 OLB's must cover TE's/RB's on first and second down, at times.  They stand up on two legs most of the time and have to play in space a lot.  These are things Smith would need to work on and probably wouldn't be effective at immediately.

So what's another way to make the most out of a player like Aldon Smith?

Oh yeah, and what abou the nose tackle (NT) position?  Franklin could be gone and Ricky Jean-Francois was underwhelming as a traditional 2-gapping 3-4 NT last year.  Why didn't we draft a NT prospect, a space-eater to play the middle of our defense?

I can give you a proposal that would take care of all of these questions, and I will...after the jump.

I had been asking a lot of questions about 3-4 defenses and the scheme variations between one team's 3-4 and another's.  I found where Greg Cosell mentioned how Aldon Smith could likely be used in a DeMarcus Ware type role.  Cosell also said that Wade Phillips defense, which he'll bring to Houston, was basically a 4-3 "under" front.  He mentioned how this would suit Mario Williams, since he's not a traditional 3-4 OLB who you want covering receivers in the pass game or playing in a ton of space.

This got me researching the 4-3 over/under fronts.  In asking around Twitter, like I love to do, I was referred to this link from SBN's own Battle Red Blog.  As I read the piece I immediately noticed how this scheme is VERY similar to a 3-4 in terms of inside linebacker alignment and responsibilities, as well as the skillsets needed by each position.


I could instantly substitute a 49ers player name into the text in place of the Texan that was named originally.  Read the quoted bits below to see what I mean:

Typically, the 2 best players on your 4-3 under need to be your weak side DE and your SAM linebacker. Conveniently, we have Mario Williams [Aldon Smith] as our uncovered DE and have newly selected Brian Cushing to play SAM. The uncovered DE in the 4-3 under needs to be an absolute beast, being able to take advantage of 1-on-1 matchups in all pass rushing situations while also being the primary contain on outside runs to the weak side. We have a DE who had double digit sacks while being triple teamed - now he is going to see 1-on-1 a lot unless teams are willing to run 2 TE sets all the time. That makes me very happy.

Now, obviously I couldn't substitute for the SAM, because that would probably be Manny Lawson, maybe, or a player we haven't yet identified.  Read on though:

Inside the SAM, you need to have a powerful run-stopping LDE. Not coincidentally, we happened to acquire Antonio Smith [Isaac Sopoaga], certified awesome-run stopping DE. He needs to be able to always occupy the strong side offensive tackle and not be reached or washed out by the strong side guard, who is left uncovered. He is going to catch a lot of single blocks from the RT, or trey blocks from the T and TE, with the FB trying to spill the SAM to open up the inside run.

 Sounds like a strong-side 5-tech, right?  A guy like Soap who can hold the point but isn't going to penetrate or get much pass rush, just be stout and play the run.  It get's better:

Your weak side DT needs to be a premier pass rusher [Justin Smith]. Being positioned on the backside 3-gap with a DE right outside him makes it very difficult for the offense to double team him. A center-guard double team would require the guard to cross his face and leave the 1 technique in open space, while a guard-tackle double team would leave Mario Williams [Aldon Smith] free. Both unfavorable.

Next is another key to me, someone on the roster who might not be a typical 3-4 two-gapping nose tackle, but could fit in perfectly into a one-gap DT:

The 1 technique is vital to the success of this defense. We happen to not have any fully qualified 1 technique DT. In this scheme, the strong side DT needs to be very big and powerful, able to withstand constant double teams, as he is essentially occupying the center and strong side guard to keep the others free. [Ricky Jean-Francois]

Now, I know RJF was bullied up a bit in Green Bay last year, but he was trying to be Aubrayo Franklin and make plays on either side of him, in both gaps.  As a 1-gapper he'd play more like he did at LSU as a 3-technique: hit your gap and disrupt, make them double team you.  A few other guys could possibly play here too, guys who are just situational guys in our current 3-4 scheme.

The MLB primarily lines up 3-4 yards deep over the play side 3 technique, and his job is to shed that guard and make plays, crush FB isos, and scrape over the top to the play if its outside. In cover one, he will usually be manned up with the first back out to the TE side. DeMeco Ryans [Takeo Spikes, eventually Navorro Bowman] at this position is great, as it allows him to attack the line of scrimmage on run plays. His first step is always downhill, looking to blow someone up. If the back he is supposed to cover stays into block, he has the option of blitzing or of setting into a little mid-hook zone, to help deter drags, slants, and curls.

Finally, the last piece of the puzzle is a guy who I think could possibly handle these duties:

You weakside linebacker in the 4-3 under needs to be your fastest and best coverage linebacker, as he is protected by the defensive lineman in front of him and therefore must be able to get anywhere on the field pretty darn quick. He has control of the backside A (1) gap, and will either shoot the gap on inside runs or scrape over on outside runs. If the play is to his side, he is the primary pursuit to the outside as well. On coverage situations, he generally plays short middle and helps out where he needs to be. Adibi [Patrick freaking Willis], due to his speed and coverage skills, is a great WLB for the 4-3 Under. He will be allowed to make more plays because he will be harassed significantly less by offensive lineman.

So, to sum'll notice that not only is the scheme similar to the 3-4 in many ways, but the skillsets required by each position seem to perfectly fit the personnel on the team.  It won't be a complete scheme-change because of this.  Responsibilities are still very similar, perhaps simplified even.

Aldon Smith would be allowed to essentially play DE from a 2-point stance (or 3-point at times) and rush the passer, play contain on runs to the weak-side, and occasionally drop back into short coverage on zone-blitz plays.  Remember, Aldon is great rushing inside as well.  Since he's on the end of the line next to Justin Smith, the two can stunt (cross each other after the snap), giving Aldon a chance to abuse guards on the inside too.

Can you imagine having to stop Aldon and Justin Smith, the Mizzou brothers, with just a guard and a tackle?  You wont, and a RB will have to come chip or help.  Now if you blitz Willis or Spikes/Bowman up the gut, there's no back to protect the QB from the free rush.

The possibilities are endless and I think this scheme best-suits the 49ers at this point.  Whether or not it's the way Fangio goes remains to be seen...but it sure is fun to think about.