Jose has a long-standing friendship with Rafa and his coach, mentor, and uncle, Toni Nadal. He knows Toni's philosophy of the game, and what he did to express it through Rafa. Jose has this one drill he puts kids through that consists of a series of forehands, the last of which calls for the youngster to take a ball that's very low and close to the net. He has to dig the ball out and fire it back over the net, but with enough topspin to make it fall within the court. It's a drill that Rafa did relentlessly, since the time he was about ten.
Many of our top private, developmental coaches, like Robert Lansdorp, are big on penetration—hit flat and clean and try to get an opponent back on his or her heels. The main problem with that approach is that when you get pushed behind your own baseline, you're out of options. I've watched Andre Agassi in slow motion, and could see that the further back he was pushed, the more spin he applied, to give him a more forgiving margin of error as well as to buy time. But that's a very defensive approach.
In our program, we like to develop an ability we call going "in and out." A player needs to know what to do when he's moving in aggressively, or finds himself getting pushed back, or out. It applies to moving and hitting side-to-side as well. The idea is that you play tennis in a circle, and you need to develop sound technique for this 360-degree job. Today's players have to know how to turn the tables and seize the initiative from all points on the court. Net clearance is a big issue for Jose: the farther back you are on the court, the more height you want on the ball crossing the net. The closer you are to the net, the less clearance you want.
We also emphasize decision making under duress. When you're playing in a circle, you need to decide if you're on defense or offense, if you ought to play high or low over the net, if you're better off volleying short, or punching the ball deep. Hit the volley deep and there's a chance the other guy will be able to make his passing shot dip low over the net, forcing you to hit a defensive volley. But if you play the volley short, your opponent has to come up with the ball but still hit it with enough pace and spin to pass you and drop it into your court.
Jose also does these "progression" drills. He'll take a young kid, stand on the same side of the net, and hand-feed him balls. He literally takes the kid—and he did this even with Roger Federer, whom Jose briefly coached shortly before coming on board with the USTA—and tosses a variety of balls in succession. The kid, or superstar, can hit any shot he wants, as hard or gently as he likes.
Jose makes the player run up, or go back. Go to this side or that. What do you do with any given ball? It's all based on decision making and footwork. Sometimes Jose will toss the ball very close to the player, so he has to move away from it before he hits. And because it's a hand feed, you have to make your own pace for whatever shot you choose. That's where racket acceleration enters the picture.