12-Point Tiebreaker
In a 12-point tiebreaker, the player or team that wins 7 points and is ahead by at least 2 points wins the tiebreaker and, therefore, a set. The score is called out as 1, 2, 3, 4, and so on throughout the game. A final tiebreaker score might be 7-0, 7-1, 7-2, 7-3, 7-4, 7-5, 8-6, 9-7, and so on (in points played). The set score would then be 7-6 or 6-7.
The singles player (or the player on the doubles team) whose turn it is to serve, serves the first point of the tiebreaker. The first server serves the first point from the right side of the court. The opponent then serves the second and third points, and after that, players serve alternately for 2 consecutive points until the winner of the tiebreak game and set has been decided. The second server serves the second and third points from the left and right courts, respectively, and this alternating-service system continues until the tiebreak game is completed.
Players change ends of the court after every 6 points and at the end of the tiebreaker. The player or team that served first in the tiebreak game receives in the first game of the next set.
Tennis: Steps to Success Jim Brown,Camille Soulier