Empty set
What is empty set in football?
The empty set is the offensive formation used for passing plays, as there are no players in the backfield except the quarterback. Such formation replaces the backfield performers with additional receivers that trouble the defense.
This formation gives the space for the quarterback to pass. In this case, the defense must concentrate the players on one matchup while the QB may address the ball to the open receiver, which may create a mismatch. This approach is effective against man coverage.
The zone defense is effective as the team spreads through the single field’s part. This manner increases the chances of catching the receiver. But nobody guarantees that the actual offender will guarantee the lateral pass addressing the receiver who ignores the defensive overwhelm and runs to gain the yardage.