What is Cover 2?
The bottom Cover 2 is a zone defence, meaning that each defender is responsible for a specific field area rather than a particular player. The field has two deep zones and five shallow zones. The bottom fifths are occupied by two corners and three linebackers. The deep halves are played by the two safeties. The two-deep, five-under Cover 2 zone defence is used by professional teams with both base and sub-package (dime, nickel) players. The reason can rush four and drop seven into coverage to stop vertical plays and push the ball to the flat or check-down (while keeping an eye on the quarterback). The Tampa 2 scheme is the most prevalent two-deep shell in the NFL. The Mike linebacker runs the inside vertical seam, giving the impression that the defence has three levels.

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