The biggest weakness of a box-and-one defense is its vulnerability to a pass to the middle of the "box". As there is no defensive player responsible for this area of the court, offensive teams are able to exploit the gap. A pass to the middle of the box or to the top of the box will generally yield a short-range shot from inside the key. Or, it will “collapse” the box, causing the four zone defenders to fall inside the key and, upon a second pass, yielding a wide open and uncontested look from the perimeter. It is for this reason that the box-and-one defense is not often seen in professional leagues.