Now let’s talk about some other points of serve. First, you must control where the ball bounces. From the left diagram, the first bounce of a deep serve should be as closer to the end line on your side as better. From the right diagram, the first bounce of a short serve should be as closer to the middle part as better. Second, the point where your racket contacts the ball must be as closer to your body as better. It can not be far away from your body. This ensures that your body and forearm impart maximized power onto the ball. On the other hand, you need to combine efficiently the forces from yourself and the dropping ball. You need to find the best position to allow the racket contact the ball. Not too high, not too low, not too forwards, not too backwards. Once you find your best contact position, you can combine your force and the dropping force of ball properly and efficiently. The third point is an advanced skill. You must strike, or knock, the ball when you serve. Every serve must involve the action of strike, or knock. Specifically, the action of strike, or knock, is an abrupt acceleration. Jan-Ove Waldner knows this point very well. With the element of strike, or knock, the serve will be explosive. This is a truly advanced skill. The coaches training young kids can give it a try.
One more point about serve is that think before you practice how to serve. LIU Guoliang said that one improves his/her serve by mainly thinking instead of only practices. The key is to design your serves and then work it out. Without thinking and design, you can not improve your serve a lot. One Chinese player knows a special serve skill to perform both deep and short serves with the same first bounce location near the end line. The skill is very difficult. With the skill, the opponent would be confused about whether or not the serve is deep. Another advanced serve skill is about side-topspin. After I rub the ball with side-topspin, I lower my center of body weight and take back my hand a little bit. By doing this, the second bounce of the ball will be lower and the opponent feels the ball drops downwards. Normally, the second bounce of side-topspin ball is high and the opponent feels the ball bounce upwards. Waldner and LIU Guoliang performs the skill well, and this is a highly advanced serve skill.