If you are the server's partner at the net and the serve lands anywhere from the middle of the box to the center service line, make a diagonal move towards the middle of the court.
Most returners are not likely to hit the return towards your alley if the serve is hit well and in this area. If they hit a return that floats at all, you will be in a position to reach it and hit the ball offensively. You can also do this as the returner's partner starting at the service line. If the return is hit past the net player and inside the singles court, move towards the middle and the net as I described for the server's partner.
It is very important to split step just prior to the opponent hitting the ball in both of these situations. This will allow you to react to the direction that your opponent hits their shot and cover the area that you just moved from.
Stepping to the middle when the ball is hit near the center of the court will force your opponent to hit a more difficult shot, allowing you to be more aggressive at the net, and putting pressure on your opponents with your movement.
Steve Annacone, USPTA Elite Pro, is the Director of Annacone Tennis (http://www.annaconetennis.com) and MyHamptonsPro based in Sag Harbor, NY (http://www. myhamptonspro.com) and Tennis Professional at Ventana Canyon Golf and Racquet Club in Tucson, AZ. For details on lessons, clinics, or coaching, contact Steve at email@example.com or call 865-300-7323