Volleyball drill: playing tennis with 2 balls

• 2 rows per field
• 1st row has ball which is thrown over the net
• 2nd row holds a ball for the 3rd person. When it is his turn he throws his ball over the net when the other ball is played on the other side and then plays the ball from the other side over the net as well.
• Continue until the ball falls

To make it more difficult more balls can be brought in or assignments can be given.