Guarding the dribble in basketball has a great deal to do with being able to slide and move laterally. The player needs to be able to quickly push off either foot to cut the defender off. Being able to do this means that the player needs to have an explosive first couple of steps.
For this defensive basketball drill you are going to add a resistance band to the equation. This will force the player to be even more explosive, and once the band is removed they will be even quicker. It is key though that the player is maintaining correct form in their slide, and that their mechanics do not suffer.