Coverages
Tampa 2
A Cover 2 shell where the middle linebacker carries the deep middle, closing the seam.
Tampa 2 keeps the two-deep safety shell but sends the middle linebacker up the field to carry the deep middle. That closes the seam window a standard Cover 2 leaves open and effectively turns two deep defenders into three.
It asks a great deal of the middle linebacker, who must be fast enough to run with tight ends and receivers down the middle of the field.