Warm-up is not practice

A player should provide the opponent a 5- minute warm-up (ten minutes if there are no ball persons). If a player refuses to warm-up the opponent, the player forfeits the right to a warm-up. Some players confuse warm-up and practice. A player should make a special effort to hit shots directly to the opponent. (If partners want to warm each other up while their opponents are warming up, they may do so.)

Warm-up serves

Take all your warm-up serves before the first serve of the match. Courtesy dictates that you not practice your service return when your opponent practices serving. If a player has completed the players warmup serves, the player shall return warm-up serves directly to the opponent.