The two-two-one half-court zone defense is a good basic defense from which to employ half-court trapping procedures coupled with a good fast-break. It is a good defense against teams that work for close-in shots; however, it is weak at the top of the key. Therefore, the two front players must sag to prevent good shooting opportunities from that area.
This is an aggressive defense that can be used well by a small, but fast team, with one big rebounder. In the following diagram X5 is the position for that big rebounder.