There is nothing more deadly to a team's defense than a player who can dribble drive into the key. It causes a number of issues. It exposes help defense and creates a number of open shots. At the end of games you’ll notice a number of teams going to a spread formation where players who are good off the dribble can really take their man to the basket and cause problems.
This past weekend St. John's absolutely dismantled Duke at Madison Square Garden. If you watched the highlights at all you noticed that St. John's did its damage by getting Duke in the open space. That means that St. John's created 1-on-1 situations with the Duke players far away from the basket. They created space so that Duke couldn’t easily help when they penetrated, and it left for a lot of open shots and easy looks. Duke is the best team in the country but didn't look like it this past weekend. Coach Lavin had a great offensive plan that was executed very well. Duke plays man-to-man and that played right into what St. John's wanted to do. Duke got great games from Nolan Smith and Kyle Singler, but you aren’t going to give up that many points and win a lot of games.
The dribble penetration doesn’t have to come from guards and it doesn’t have to happen at the top of the key. The key is to be able to get past that first man and create help situations. When the help defense hits, then someone is open and often that help defense creates a mismatch somewhere. For example, if I dribble drive from the top and a wing player comes out to help then I kick the ball to his man who is open on the wing. In true help defense, the player that I beat should help out on that man. That’s my mismatch. He’s going to be a point guard defender guarding a bigger stronger player. This results in a great scoring opportunity for the offense, and it was all caused by simply being able to drive to the basket.
When a player penetrates, the other offensive players need to move. Too often players stand and watch instead of cutting to the basket. When someone is beating someone else it is the perfect time to cut for a layup or a simple jump shot. Never get caught standing and watching unless you are spotting up and getting in shooting position in case a pass comes your way. Many times each offense has the player cut who just got left as the result of help defense. It’s a great way to get easy baskets.