When I made the All-WAC Defensive Team, it wasn't because I blocked every shot. Most of my best defensive plays happened before my man ever touched the ball. Good post defense is about position, not reaction. If you let a strong post player catch the ball deep in the paint, you've already lost most of the battle.
Rule one: make the catch hard
Every possession, ask yourself one question: if the ball goes into the post right now, where does my player catch it? Your job is to push that catch as far from the rim as possible, or take it away completely.
Three ways to guard the post
Three-quarter (the default). Stand on the high side of the post player, between them and the ball, with your arm and leg in the passing lane. This takes away the easy entry pass from the wing and forces a lob or a bad angle. Most of the time, this is where you should be.
Front. Get completely in front of the post player, facing the ball. Use this when they're very deep in the paint or much bigger than you. It only works if your team has help on the backside, because a lob over the top is now the open pass.
Play behind. Stay between your player and the basket. Use it when they're catching far from the rim (outside the block) and aren't a threat to score from there. Keep a forearm in their back and stay low so they can't back you down.
Simple version for younger players: If the ball is on the wing, stand on the ball side of your player with your hand in the passing lane. If the ball goes to the top of the key, step around in front to stay in that same spot.
Moving when the ball moves
The ball moves faster than you can. The best post defenders move every time a pass is in the air, not after it's caught.
- Step through, not around. When you switch sides, step in front of the offensive player rather than going behind them. Going behind gives them a free step to seal you.
- Keep contact. A hand or forearm on the offensive player tells you where they are without looking away from the ball.
- Talk. Tell your help defender if you're fronting. They need to know the lob is coming.
If they catch it anyway
It happens. Now the goal changes: don't foul and don't give up the easy one.
- Get low and wide, chest up, arms up and straight. Officials reward verticality.
- Don't reach for the ball. Reaching pulls you off balance and puts them on the free-throw line.
- Take away the middle. Force them toward the baseline, where help is coming and the angle is worse.
- Contest every shot with a straight hand, then box out. A tough miss only counts if you get the rebound.
A drill to build the habit
Have a passer on the wing and another at the top. The post player moves between the blocks; the defender has to stay three-quartered on the ball side as the ball swings back and forth. Every time the defender is on the wrong side when a pass is thrown, the post player gets the ball and plays one-on-one. Players figure out quickly that the work before the catch is the easy part.