You use it depending on which hash of the field you're on. If you're on the right hash mark, you'll want your linebackers playing the strong side of the field.
4-3 Over is good when you're on the right hash mark in passing downs because you'll have your FS on the strong side of the formation.
4-3 Under is the same, just the opposite hash mark.
Each of these you can flip your SS/FS so you can bring more run support to the strong side of the field.
4-3 Over plus I don't really use but it has some decent zone blitzes for when you're on the left hash mark.
4-3 Stack is a good middle of the field defense for defending 0-3 WR/TE. It offers the most plays I believe and has a host of zone blitzes. Be careful with zero coverage in this formation though as I've been eaten up by TE's many a time.
EDIT: Found more info for OP
I found an even better explanation over at simsports. Great write up by user OneBack
I'm probably going to get a little technical here, but bear with me and if you don't understand fully please ask questions, but I'm putting together a video that will probably answer these questions a little better than me typing at work.
Quote Originally Posted by tservo75 View Post
Hello,
I need some help when it comes to defensive playcalling, because I don't believe the "Ask Coach" always gives such wise information. I know I have a lot of questions, but ANY help is much appreciated...
1. If I choose 4-3, how do I decide whether to choose over, under, stack, etc.?
Over and Under are virtually the same defense in the way that I use them in the game, there are some different plays in each formation so I'll switch between the two due to that fact.
The general rule on when to use Over/Under and Stack 43 is if there are two back in the backfield use over/under, if there is one back in the backfield, use stack. The mose basic reason is with stack there are three bubbles (area between defensive linemen where a linebacker is aligned) at 50 (strong side linebacker), 10 (Middle linebacker) and 30 (Weak linebacker, whereas with an Over/Under front you have two bubbles at 30 (Middle linebacker) and 10 (Weak linebacker).
Great, but what does that mean?
Bascially in the running game offenses want to attack bubbles and with two backs in the backfield they are declaring this is a running formation, can they pass, certainly, but they are not able to attack a defense in the same number of ways if they aligned with a 2nd TE or a 3rd WR. So why provide an easier path with a stack defense. I'll explain further in a video but that's the basic jist of it.
Quote Originally Posted by tservo75 View Post
2. What do the different zone coverages mean, and when to choose each?
The different Zone coverages in the game are based around the number of deep players, for example Cover 2 is a two deep, five under coverage. Cover 3 is three deep, four under coverage and Cover 4 is four deep, 3 under coverage.
What coverage to call is a complex question as its highly dependant on the offensive formation and what they are trying to accomplish from said formation. But in the most basic form here's a starting list, the frist set of numbers is the number of recievers to a side not counting the backfield then the coverage:
2X1 - Cover 1, Cover 2 Man or Zone, Cover 2 Sink if the #2 reciever is detached, Cover 3, Cover 4
2x2 - Cover 2 Man or Zone, Cover 2 Sink, Cover 4
3X1 - Cover 4
3X2 - Cover 0 Blitz, Cover 1 Blitz, Cover 3, Cover 4
While there are some roots in real life here there are some consessions made for the game and this is a very basic list.
Quote Originally Posted by tservo75 View Post
3. If I want to take away a specific receiver, should I "spotlight" him, send the zone in that direction? What does "spotlight" do anyway?
I haven't played around with spotlight that much this year, however when playing a zone defense the zone defender will react quicker to a spotlighted receiver than a non-spotlighted receiver, they problem last year was that not only would the closest defender react but so would any defender on that side of the field. You can certainly use the spotlight function to slow down/stop a reciever however the best way I've found to slow down a receiver is to change up the coverages and make sure you either high/low the reciever or in/out the reciever with defenders.
Quote Originally Posted by tservo75 View Post
4. What plays are best in taking away the option?
Probably the best way this year is to change the option game planning setting to Aggressive - then manually defend the HB/Pitch man.
Quote Originally Posted by tservo75 View Post
5. General defensive playcalling advice.
I tried strategy guides in the past, but I found they just tell you how to run Play X against Play Y and say very little about actual strategy.
Thanks in advance!
Get the basics down (above), ask questions, and get good at manually using a defender to take away the middle of the field.
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