The arrival of New Orleans Saints defensive coordinator Steve Spagnuolo meant a change in the culture and scheme of the defense, namely the “zone defense”. For those that are not aware, let’s look at what a zone defense is.
The zone defense simply put is a defensive scheme that requires the defensive backs(cornerbacks & safeties) and linebackers to work different areas or “zones” on the field.
Of course the cornerbacks and safeties are mainly responsible for deeper zones than the linebackers who are responsible for the shorter to mid-range passes. While this occurs, the defensive lineman are applying pressure on the quarterback.
With pressure on the quarterback being applied and proper coverage is being given by the linebackers and defensive backs, it makes it more difficult for the quarterback to find a receiver.
If the quarterback is unable to find a receiver and the defensive lineman are able to collapse the pocket and/or get to him, a sack or a rushed decision that leads to an interception is the ultimate prize.
One option that is also available is to send one or, in extreme cases, two linebackers to blitz the quarterback. With any linebacker blitzing, it requires the other linebackers to split the difference and help absorb the zone left open.