Consider the two cardinal rules of winning tennis - get the ball in play, and always be prepared for the return.

Said from the opposite perspective - players lose because of errors, or from failing to prepare for the next shot. But just for the moment, let's assume that you have learned to reduce your own errors, and equally have mastered preparing for the opponent's reply.

At this point you begin to employ tactics, opening the court, playing angles, varying length, speed and spin.

But I believe the following two frequently overlooked factors may encourage you to add the drop shot to your tennis toolbox.

1. Tennis court dimensions - singles court 27 feet wide, 78 feet deep.
Run the opponent from the center to the sideline - 13.5 feet.
Run the opponent from corner to corner, the most common tactic - 27 feet (more or less).
Run the opponent from the baseline to the net (with an average drop shot - 30 plus feet.
Run the opponent from behind the baseline to the net with a good drop shot - 35 feet plus.

2. General practice patterns (whether in lessons, hitting with one another, or using the ball machine) - most players hone their ground strokes, and overlook approach shots, volleys and overheads. So if your tactics move the oppponent from side to side you play into their strengths. But if your tactics vary from deep to short, you move your opponent to unpracticed areas of the court.

Said another way, if your opponent prefers the baseline, then move them forward.

Andy please note - and also during the first set and I repeat the first set,it was said on Canal + here is Spain by Jordi Arresse that he had never seen a player in a Grand Slam final give out so many "negative signs to his opponent" than Andy gave to Novak.