This is a great defensive drill. It is complex because the defender uses many elements of individual and team defence: stopping the penetrator from the help side, closing out, playing 1v1 with the offensive player who receives the ball, boxing out when a shot is taken, and ball side defence,when his man gets the ball.
Picture 1: O1 takes the shot, O3 goes to the rebound - X1 must box out and grab the rebound.
Picture 2: When O1 drives to the basket X1 who is in the help position must stop him.
Picture 3: O3 receives the ball from O1, X1 must close out and play 1v1 defence against O3 who has the ball.
Picture 4: O3 goes to the ball side to receive the ball, and X1 must cover the passing lane and play 1v1 when O3 receives the ball.

Defence.

Have players use their peripherial vision - they must seen their man and the ball.