To simulate a breakdown in play pretend an opponent man is on the baseline about 2 meters away from the key opposite the ball handler.
The objective is to make the offensive player to take a shot outside of the key.
Chairs or bins can be placed on the wings to open up peripheral vision.
Turning to run, not glide into the help position.
Try to simulate picking up the ball handler before he enters the lane.
Defend the ball handler who is moving forward at speed.
Give ground by initially going backwards.
Block the shot and block out the rebound.
Do this drill 6 times on each side of the key.
The tendency when players go to help is to put both hands fully extended above their head, stand straight up, feet together and hope that the offensive player will run into them.
Good team defence is five players guarding the ball, not five separate one-on-ones. The shell drill is where that starts, so here is how to teach help-side positioning and rotations from the first week of the season.
Rebounding is the least glamorous thing in basketball and one of the most decisive. It is also almost entirely a habit, which means it is entirely coachable.
Good spacing is only the start. The best modern offences teach players to attack the defence's rotations and play in a permanent 4-on-3 - here is how to coach that read.