The 4-2-5 Defense is basically the same as the 4-4 Defense except that we will be calling the two Outside Linebackers as the Strong Safety and the Weak Safety. Otherwise, there is no real difference between the 4-2-5 and the 4-4 defense. The following discussion will be about the base alignment of the 4-2-5.
On the Strong Side, we’re going to have a Tackle in a strong 3-Technique. Then we’re going to have an End at the 7 which is shaded inside the Tight End. If we’ve got a very good End, we could technically look like we’re strong enough.
We have the Mike Linebacker in a 30-Technique, outside shade of the Guard and 5 yards off the ball. This is where we’ll play A-gap.
The Strong Safety should be 3×3 off the End Man on the Line of Scrimmage (EMOLS). He’s our box player so he’ll run and we’re going to make sure that he’s going to force to play back to the inside.
On the Weak Side, we’ve got a Tackle in a 1-Technique. He’s going to handle the A-gap. Our Will Linebacker is going to be in a 30-Technique outside shade of the Guard. He’s going to handle the B-gap to his side. If we shift the two Tackles over, we can let Will run a 4-2-5 and give Mike a little more responsibility. These all depends on the types of players that we have.
Our End is going to be 50 outside shade of the Weak Side. Take your best athlete. You don’t need to know a lot and you don’t want to have to think too much. Put him on that Weak Side and then let him go. That’s a great spot to put somebody who is a great athlete. He may not be a true Defensive Lineman and may not be down to split double teams but he must be someone who can really run and can put pressure on the passer. We’re going to cut this guy loose and just let him go.
The Weak Safety is our box player on the Weak Side. The 4-2-5 defense is an 8-man front which means that we should be running some sort of a Cover 3 shell behind it as our base. Whether we’re running a one high, a man coverage, or a Cover 3, any of these is going to fit well with 4-2-5.
You can work things like a Cover 2 or Quarters Coverage with the 4-2-5 but it is not structurally setup for that. The simplest thing you can do is run a Cover 3. You could still adjust to all the formations when you get your doubles and your trips.
You’re going to have to take some time to teach the Weak Safety how to collision and carry a #2 receiver out there. You have to teach the Cornerback how to split two receivers running verticals in his zone.
So those are the techniques that you could teach. Since you’ll have to teach a whole lot of the Linemen, you’re going to have to work with the simple basics of the 4-2-5 defense.