Decision-making skills make the difference in the game. However, only very few players reach their full potential, because training the decision-making skills is a challenging process. Virtual training tools can be directly applied to accelerate athlete development in team sports. Instead of relying on a coach and teammates to gain valuable training time, virtual training tools allow individual athletes to practice on their own at any time of the day, even when recovering from injury. It is now possible for us to measure the behavior of the athlete in real time in order to understand the training progress of the athlete and to provide direct feedback.