Every tennis player, from weekend hacker to national champion, feels pressure on the court. The best remedy may be to stay in motion. Nervousness can be turned to your advantage, but only if it doesn't inhibit your mobility.
Knowing he was going to be tense in a big match, Arthur Ashe used to leave a note by his chair on the sideline so he'd see it each time he changed ends. It said simply: ''Keep your feet moving.''
Ashe realized the first failing under pressure is to freeze and stop getting a jump on the ball. Movement begins with good footwork, so he reasoned that if he could keep his feet going he could deal with any stress he felt.
Watch the better player and you'll see that his feet almost never stop moving. That isn't a sign of being too keyed up. It's a sign of using this situation to advantage.