Coach passes the ball to one of the three offensive players who stay put. There is no scoring, passing or attacking in this drill. This drill simply emphasises how the defenders should position themselves in a man to man defence.
Picture 1: The coach passes to O2, so X2 defender makes a good close out and plays on-ball defence. X1 sprints out into a denial position (one pass away from the ball), and assumes a position a little up the line and a step or two toward the ball (to prevent not only the pass, but dribble penetration). X3 sprints out to play helpside defence, dropping down into the key (two passes away from the ball). The coach makes any corrections in the players alignment, and then the ball is passed back to the coach for the next three defenders in line. The current defenders become offence and the offensive players go to the back of the defensive lines.

Find the right postion on defence.

The coach pass to the point, and X1 sprints out and makes a good close out, while the two wing defenders sprint out into denial defence.