Just to help clarify. It is not as simple as saying Miami should play a 4-3, a 3-4, or a 3-3. Conceptually, when a team is multiple in defense the coverage determine the front. As a remnant of the days when offenses were primarily defined by the running game, coaches named the defenses according to the number of run defenders aka the front (ie the numbers of DL & LB: 4-3, 3-3, 3-4, 5-3.) However, with the reliance on the passing attack at all levels, this method is now inefficient.
Today, it is more efficient to think about defenses from the back, forward. In other words, the coverage you use sets the front. You can only have 11 guys on the field at any given time. Therefore, if you want to keep 4 guys (2S & 2 CB) back in pass defense, you HAVE to play some version of a 7 man front (4-3, 3-4, 5-2, 6-1.) The difference between a 3-4 & a 4-3 is largely a personnel issue (certain skills are better than others for each defense) but both can be characterized as a 7 man front and both can be effective.
Defense is all about simple arithmetic. 5 OL & 1 TE create 7 possible gaps for a RB to run through that need to be filled by a defender. Therefore, any 7 man front (3-4, 4-3, 5-2...) is OK against 5 OL, 1 TE, 1 RB, 2 WR formations; the numbers work. 7 defenders & 7 gaps.
The problem becomes when you add another TE or a fullback, there are now 8 possible gaps and only 7 defenders to fill them. To get the “math” to work, 1 defender (DL or LB) must be responsible for 2 gaps, which requires much more skill. Warren Sapp was a great 2 gap DT. Brian Urlacher is a great 2 gapping MLB. Doesn't matter who "2 Gaps" but you better have a stud because it requires him to do the job of 2.
The alternative is to sacrifice one of your pass defenders to play an 8 man front (4-4, 5-3, 3-5) but that leaves you susceptible to the offense sending any combination of its 4 eligible receivers (WR, TE, FB, RB) into the pass pattern. That is the real reason 2 pass catching TE's cause problems for any 7 man front: 8 running gaps and still have 4 eligible pass catchers on the line of scrimmage. Coincidentally, that is what makes the flexbone, or double-wing formations, particularly dangerous at the high school and some college level: 8 running gaps with 4 potential vertical threats. Teams spend countless hours teaching those TE or wings to give the appearance of run blocking then release into pass routes.
With the emergence of “hybrid” offensive players (the HUGE FAST WR that can block: Calvin Johnson, the pass catching RB (Darren Sproles), the dual threat QB (RG3), the blocking/receiving TE (Tony Gonzales/Jimmy Graham) defenses had to match. The DB who runs like a CB but tackles like a LB (Tyrann Mathieu, Calvin Prior, Terrance Brooks, Sean Spence.) The LB that takes on blockers like a DT but runs like a DB (Ray Lewis/Urlacher.) These guys allow defensive coordinators more flexibility to have dual run/pass roles.
This was a very long winded way of saying that a good defensive coordinator will show 4-3 & 4-3 looks just to confuse blocking schemes. But he also may show a 3-5-3, a 3-3-5, and the 4-2-5, which is ran with more of a hybrid safety player. The reason the 3-5-3/3-3-5 and 4-2-5 are so popular is that with the right players, those extra LBs or DBs can easily shift to show a 6 man front with 5 in coverage, a 7 man front with 4 in coverage, 8 man front with 3 in coverage, or a 9 man front with 2 in coverage. Often times this shift is very late and can present a “false” look to the QB. A good Defensive Coordinator at Miami would (an has always) place emphasis on speed over size which really helps this philosophy.
Go Canes
