Backgammon

The tournament season, and in particular the World Championships in Monte Carlo, are upon us, so tournament play will be the theme of our next few articles. Tournament matches, as you probably know, are won by the first to reach a specified number of points. A weekly club tournament will typically be to 7 points while the finals of major tournaments are played to 25 points or more. A newer format is to play the best of five 9-point matches.

When one player reaches match point the next game is played without the doubling cube in use. This is known as the "Crawford Game", named after John Crawford who introduced the rule to reduce some of the bias in favour of the trailing player. This bias occurs because the trailer will double on the first move of each game after his opponent reaches match point. Thus the trailer will win 2 or 4 points on each game and he risks nothing by doubling because if he loses the game he loses the match.

Unlike money play, where each game can be treated on its own merits, in match play the score is paramount and, particularly in the later stages of a match, both cube action and move selection can be dictated by the score. As a simple example, suppose that in a match to 7 points you are leading 6-5 after the Crawford Game. Your opponent opens with a 31, making his 5-point. You roll 63 and play 24/15. Your opponent doubles - do you take? The answer is a very clear no. If you take, this will be the last game of the match and you will be at a distinct disadvantage. If you drop, the next game will be the last but at least you will have the chance of winning the opening roll. Whenever your opponent has an odd number of points post-Crawford, you always have the option of exercising what is known as your free drop.

However, if the score is 6-4 and the same sequence occurs then you must take. At 6-4 your opponent needs to win two games to win the match, you can't afford to give him one of those games for nothing.

As an example of the score dictating move strategy let's suppose you lead 6-3 post-Crawford. How would you play an opening 32? Requiring only a simple win you should steer for a simple position and play 24/21, 13/11. If, however, you trailed 3-6 and rolled 32 then you must play 13/10, 13/11. You would love to win a gammon (it would win the match for you) and playing 13/10, 13/11 leads to more prime v prime games and generates far more gammons than 24/21, 13/11.