Tennis is a sport that requires mental strength as much as it does with physical strength. Top players are intelligent players who understand how the game works. Knowing how to use your brain can really help your game and take you to another level. For example, during the pre-match warm up with your opponent, observe how your opponent hits the ball. Notice which grip your opponent is hitting with. Certain grips produce certain shots – seeing how your opponent holds the racket for a particular stroke can help you deduce a way to counter that shot and devise a strategy. (e.g. players with a Continental grip for a forehand have a hard time with high shots; or players with a Western grip for a forehand have a hard time with low shots). Observe the backhand as well. If your opponent has a weak backhand then it is good idea to focus on that side during the match.
Try to find out as much as you can about your opponent’s style of play during the warm up. Does your opponent practice his volleys or request lobs to hit overheads during the warmup, or does he mainly stick to the baseline? How does he move? How fast is his first serve and is it consistent? Once you have answered these questions, come up with a game plan as to how you are going to win the match. Utilizing the pre-match warm up time to observe your opponent and coming up with a strategy can make the difference in winning and losing a match.