The focus of the drill is having the proper stance you need off ball to affect the cleanliness and the speed with which a skip pass can get through the middle of your defense. There are 2 players in the perimeter with 1 player in the middle who is going to try and affect the skip passes from the perimeter players. The perimeter players are limited to a few yards to their sides, trying to pass the ball to each other while the player in the middle tries to stop them. You decide how many seconds the perimeter players can carry before passing and limit the number of passes before moving to the next set of players.