By: Ian BoydIf you read Chris Brown and examined his “Essential Smart Football” you’ll have read about Charlie Strong and the innovation of the 3-3-5 defense . If you ever frequent Brophy’s football blog you may have read about Strong’s Cover-3 pattern matching and favored zone-blitzes However, there hasn’t been a great deal of focus on what Strong’s defense at Texas will look like. Many Texas fans, not having spent a great deal of time watching Louisville games, have latched onto the “3-3-5” and whatever they know of that scheme as a guideline for what to expect from Texas. Don’t worry, we’ll sort all this out for you.Charlie Strong’s defense is a marriage of the 4-3 Under and its principles with the disguise and zone-blitz heavy nature of the 3-3-5.This is not terribly different from what Manny Diaz was doing at Texas. However, the subtle differences have major importance in conceptualizing the system. While Diaz often got in the habit of throwing blitzes at the wall hoping something would stick and inflict a negative play to kill a drive, Strong’s utilization of stunting and blitzing flows first from his base defense, the 4-3 Under.Because Strong’s defenders have a base defense, philosophy, and rules that they follow, the addition of movement, blitzing, and complexity is easier to absorb. Much like how a few extra drinks have less impact after a big dinner, Strong’s defenders can hold their liquor running exotic calls against an up-tempo spread because of their digestion of the basic rules.The principles of the 4-3 Under amount to creating pressure on the line of scrimmage, maintaining leverage by keeping the ball “inside and in front,” and bringing extra run defenders to allow linebackers to fly to the ball.The term “Under” refers to the way in which the defensive line is shifted away from the strength of an offensive formation while the linebackers are shifted towards it.Classically, that looks like this:Against the spread offenses of the B12, that will typically look more like the Sam aligning to the wide side of the field and the passing strength while the Rover sets up on the boundary, and the nose tackle lines up across from the running back.Ideally this results in weakside runs working uphill having to go against your 3-tech defensive tackle while strong side runs are funneled inside by the Sam and then brought down by the Mike and Will’s aggressive run fills. The nose has to be able to handle a double team and protect the linebackers while a safety is dropped down to handle backside cuts that emerge as a result of hard flow by the linebackers.There’s arguably no better defense for taking away 2-back run plays than the 4-3 Under. The aggressive linebacker play and heavy presence across the line of scrimmage makes it hard for the offensive line to double-team defensive linemen and puts constant pressure on the offense to avoid mistakes which will inevitably lead to negative plays. The Under’s tenants have been adaptable to defensing the spread.This is the starting point for Strong’s defense and where the fundamentals and philosophy come from in creating different fronts and calls for his defense in handling opposing teams.Also key to this defense is the deployment of the linebackers. In the Strong D, their coverage roles are fairly simple. In each of the coverages, from Cover-3 to Fire Zones to the 2-deep schemes, the outside linebackers match up with the 2nd receiver from the sideline while the middle linebacker takes the third receiver. This allows the linebackers to move their eyes from the blocking flow of the OL back up to the positioning of the near running backs without getting out of position against pass or run.Whether Strong and Bedford emphasize Cover-4 or Cover-3 early on will depend on some of the fulcrum players such as the Nickel/Sam and safeties as well as the cornerbacks. Texas’ successfully played a good deal of single-deep safety coverage last year with Gerg so it’s likely that the 2014 Texas D will start there.The aggressive pattern-matching Cover-3 requires a rangy deep safety and great athletes at Corner, as witnessed in the dominant 4-3 Under defense played by Seattle’s professional team. The 2-deep coverages rely more on having great range at Nickel and safeties who can keep the ball in front of them and then close on and tackle ballcarriers closer to the line of scrimmage than the 1st down marker. Texas’ current roster is a better match for the former approach.Next we have the 3-3-5. The main goal of this scheme is to line up in an odd front (three DL) before stunting into some sort of 4-3 front that the offense won’t predict or be ready to block. Strong still utilizes this package frequently, but from the foundation of the 4-3 Under.In Louisville, Marcus Smith was the key to this approach. Louisville would line up in a variety of 3-3 or 3-4 alignments with Smith standing up and moving around before the snap. Sometimes the Cards would only bring three rushers and drop eight into coverage. They would often simply stunt into the 4-3 Under or another 4-3 front. Or they would bring a Fire Zone.The Fire Zone blitz is essentially a base defense for Strong and it offers a method to accomplish most of his aims. The Fire Zone can become like an ultra-aggressive Under front with players flying at the edges to funnel the ball inside, eight man fronts outnumbering the offense, and easy adaptation of the Cover-3 pattern-matching rules. For Strong, it’s a cheaper installation because it doesn’t defy his normal rules for defenders. He also doesn’t run an inordinately high number of them so his players are well-repped in their assignments.What is most effective about the Fire Zone for Strong is how it allows him to bring a great deal of disguise without overly complicating the defense for his players.In all of his defenses, Strong has an extra pass defender to either roam the middle (Cover-3), stay deep (Cover-4), or blitz the QB (Fire Zones). Then you have the corners, the three underneath defenders matching #2 and #3, and the deep safety(s). Which players fit where becomes the guessing game for the offense.Louisville would frequently present a 3-3-5 front to the offense with Marcus Smith lurking on the edge and the offense wouldn’t necessarily have great confidence about the defensive call that was coming. Would it be the 4-3 Under backed by a Cover-3 concept?Perhaps a 4-3 Under front with a stunt and Cover-4 behind it?Or…a Fire Zone.This was a particularly nasty Fire Zone Strong liked to call that would often get one of his linebackers a quick and free path straight into the backfield. Diaz used to utilize calls like this with Manny Acho that devastated opponents. Edwin Freeman, this is your future.Notice that Marcus Smith is a major threat to the offense in every option but he plays a different role in each. In the first example he’s a weakside pass-rusher the OT has to beat after making sure the DL across from him is neutralized. In the 2nd example he’s coming inside on an unsuspecting OG. In that last example he might well take a quick jab step at the OT before dropping back to cover the #2 receiver to his side of the field. While the OT is eyeing Smith and then handling a stunting DL (perhaps Ridgeway), the guard inside of him is matched up against two hard charging linebackers perhaps without any assistance.Many Texas fans are understandably wary of a defense that makes heavy use of Fire Zones but I hope it’s clear how useful they can be. The possibilities of where the coverage will be weak or strong, which defensive players will be matched up on different receivers and routes, and who exactly the OL will have to block are numerous but the defense remains sound and simple.Diaz got into trouble by moving his DL too often, negating their advantages had they simply played straight up, and having a defensive backfield that didn’t understand how to maintain leverage in their various assignments. Strong will keep things simpler. The goal won’t be to have an endless array of Fire Zones and stunts to attack the offense with, but simply to have a few that overlap in appearance.From there, it’s still all about execution of technique and fundamentals.Hopefully that provides everyone with a sense of how Strong bases his defense in classic rules and principles while using the 3-3-5 front and Fire Zones to allow him to mix in heavy disguise and uncertainty for the offense while making use of having versatile athletes on his roster. In the future we’ll get specific about how he combats the terrifying up-tempo spread option and discuss where different Longhorns fit into this system.