Tennis Tie-breaker

To prevent long sets, some tournaments use a tie-break system which comes into operation at a specified equal score (6-all or 8-all).
There are several systems in use within Australia and around the world.
In the "7 out of 12" version the first player to score 7 points with a 2 point lead is the winner.

If the score reaches 6-all the game continues until one player leads by 2 points.
In some tournaments the tie-break is not used in a final set, which must be played out in the ordinary way.
In the United States the favored version is for the 1st player or partnership to score 5 out of the next 9 points to be the winner.