Rally and Fault
After the serve, a rally continues until one side commits a fault resulting in a dead ball. Each team is responsible for making line calls on their side of the net. They may also ask an opponent for assistance; if the opponent saw the ball clearly and does then make a call, it is binding. If there is any doubt about whether the ball is out or in, the call should be made in favor of the opponent.
Faults include:
- either of the server's feet touches the baseline, the court, or the area outside the imaginary extensions of the centerline or sideline prior to striking the ball
- not hitting the serve into the opponent's diagonally opposite service court
- volleying the ball when returning a serve
- volleying the ball when returning the first service return
- not hitting the ball beyond the net
- not hitting the ball before it bounces twice on one side of the net
- hitting the ball so it lands out of bounds (outside the court lines)
- stepping into the non-volley zone, or touching any of lines around the non-volley zone, in the act of volleying the ball
- touching the net with any part of the body, clothing, paddle, or assistance device
- crossing the plane of the net, if not in the process of striking the ball