Let’s start with the basics. The general idea behind the 3-4 is to have three down linemen (2 DT sized ends, 1 massive NT) hold the point and take up as much space as possible. The DE’s are bigger than the average 4-3 DE by a good 30-40 pounds, with a good size being around 6’5”, 300lbs. The nose tackle is even bigger, but often times more squat because of the leverage offered by being lower to the ground. The ideal NT is around 6’3”, 340lbs. The defensive line isn’t expected to rush the passer, but rather gobble up double teams, freeing up the four linebackers to roam and make all of the plays. In the 3-4, the linebackers are the main component to the defense, making the sacks and making the tackles. The linebackers in a 3-4 are usually bigger, so that in the chance that they do engage an offensive linemen, they will have the size to man up and shed the block if the ball comes their way. This is usually hard to do for a typical 4-3 linebacker, because the size disparity of a guard can easily be 60lbs more than a 4-3 LB. If a guard reaches the second level and gets his hands on the LB, then the LB is usually toast. The corners usually play a more aggressive style of coverage, often time betting on the blitz getting to the QB to hurry his throw, so the DB’s tend to play more press than a 4-3. What are some of the more subtle benefits of a 3-4 defense though?
The 3-4 allows for a wider range of players to be selected. The 4-3 requires defensive linemen that can both rush the QB and stop the run. The 3-4 requires that the DL hold the point and take on blocks. The 4-3 requires that the linebackers be quicker and faster and requires that the LB’s play more man coverage in the passing game and slip into the gaps in the run. The 3-4 allows the linebackers to play more of a soft zone in the pass, as there are more bodies in the short to intermediate passing routes to wreak havoc. The LB’s also don’t have to be as adept at man coverage and often times may not have to be good at coverage at all, if they are the main blitzing LB. Basically put, the 4-3 requires that the front seven be good at both defending the pass and run, while the 3-4 allows for more players to specialize in a particular skill set. You’ll notice that 3-4 teams hoard linebackers, but why? Because the linebackers make the scheme work. Now on to the Jaguars.
Do the Jags have the personnel to make the 3-4 scheme work? Well, arguably, they don’t have the personnel to make the 3-4 OR 4-3 work at the moment. With the lack of a CBA, the Jags roster is thoroughly depleted. Durant and Morrison are not under contract, as are many other players. The current linebacking corp consists of Daryl Smith, Cutrera and Allen. Besides D. Smith, there is nothing special to speak of. The defensive line is there, but its a boat load of youth. The whole secondary needs retooling and the Jags need some modicum of consistency from Cox and Mathis, who can both be good, but play hot and cold.
Let’s hypothesize though, what if the Jags went to the 3-4, could it be done? Well, if we bring into account the draft, it could potentially work. Here’s how I think it could shape up if it were to happen next year (which it most likely will not happen). The starting DL would be Alualu, Knighton and Lane positioned up front. Knighton is a beast and controls the line already, Alualu has experience as a 3-4 end and Lane has the potential to grow into his frame and play well. Smith would serve as a rotational DE. The linebackers are severely lacking and the draft and free agency would have to be used to fill the ranks. Daryl Smith could play as an ILB, but the other one would be up for grabs. The OLB spots could be filled by Hart and Morgan, both of whom were projected to be 3-4 rush linebackers. The secondary needs to be fixed no matter what alignment they run.
While I have personally come to believe that the 3-4 might be easier to make really good (as the players are just easier to find), the Jaguars just currently do not possess the players necessary to effectively run it. It could happen down the line, but as for next season, don’t count on it.