Knowing what to focus on and how to maintain concentration, while resisting distractions, is what you need to learn in order to play your best tennis. You must learn how to maintain sharp focus when needed and have a broad based focus when needed. You must be able to regain concentration when it's lost during the match. When an athlete is so focused that they stop "thinking" about performing, they compete "effortlessly," this is what is referred to as "THE ZONE." The ability to focus and hold concentration on the correct aspects of your performance is probably one of the most valuable mental skills you can learn. Many other mental skills are all important parts of ultimately assisting you so that you can focus and concentrate on what is important when it is needed.