A great man to man defense is built from the ground up, and that means breaking down certain actions like being in the gap, help, communicating, etc. In order to focus on these details you need to start out with defensive breakdowns, and teach your team how to handle each type of situation. That is where the shell drill comes into play. The shell drill is going to be 4 on 4 in the half court, and it is going to allow your team to practice specific situations that you will encounter when playing man to man half court defense.
This specific shell drill is going to work on where to be in the help/gap when the ball is 1 or 2 passes away, and then also on how to handle offensive cutters. Basketball drills like this are really important for your team in learning to play defense, but they are also great for working on man to man offense as well, because they allow your players to get reps on offense too.
Drill Name: Basic and Cutters Shell Drill
Similar Drills: Down Screens and Baseline Drive Shell Drill
Drill Goal: Work on man to man half court defense.
Equipment Needed: 8+ players, a coach, and a ball.
Tips: Every time the ball moves, the defensive players should be adjusting. Think of it like a string; when the ball moves it pulls the players with it accordingly. Communication needs to be a non-negotiable on defense.
Instructions: There is going to be an offensive player on each wing and in each corner. The defensive players are going to start on the baseline. When the coach throws the ball out to one of the offensive players on the perimeter, the defensive players will closeout or get in the gap/help accordingly. The offensive players are going to move the ball around the perimeter without any dribbles, and the defensive players must adjust and communicate on every pass. After several minutes of working on this, you are going to incorporate some offensive cuts into the drill. So every time that a guard passes to a post player, they are going ball side cut and try to get the ball back. However, the defender needs to jump to the ball and take away the pass back to the cutter. When the cutter cuts, the weak side offensive players must fill up, so that the cutter can fill out to the empty opposite corner.