In a backgammon match, the strategy for doubling can be different from that of a single game. For instance, if you are behind in the match and forced into a back game with the cube at 2, you should double your opponent even though they would double you in a single game. This is because if your opponent wins the game, they will likely win a gammon anyway, and you want to increase the stakes to make a single game win more valuable for you.
On the other hand, if you are leading in a match, you should be cautious about doubling when you have a chance of winning a gammon but could still lose the game. In a single game, your opponent would likely drop the double to avoid the risk of losing 4 points, but in a match, they don’t care about losing 2 or 4 points since they will lose the match either way. If they accept the double, they will likely redouble you straight back to 4, and the match will depend on that game, regardless of whether it’s a gammon or a single game. Therefore, the right strategy is to go all out for a gammon and not to double your opponent. If your opponent does double you, you should accept it but change your tactics to avoid losing a gammon, as that would cost you the match.
Example match situation
The situation described is when the score is tied at 13-all in a match that requires 15 points to win. In this situation, the tactics with the doubling cube depend on various factors.
- If the Crawford rule is not being played, and you are ahead with a chance of a gammon, you must not double. Black will refuse if you do, and then double you in the next game. If you are behind, you do not usually double, but if you have a good chance of winning by hitting your opponent, then you must double.
If there is no chance of a gammon, and you are ahead, offer a double at once, no matter how small your advantage is. Black must refuse, and you will win a simple game and a free drop. But if you play on, giving Black a chance to win, he may get lucky and win the match.
- If the Crawford rule is being played, and you have a very good chance of a gammon, do not double. Try to win the match on this game. If you are behind, double if you have a chance of winning the game or losing a gammon. You are going to lose the match anyway if you get gammoned, so you must make sure you win the match if you do happen to win the game.
If there is no chance of a gammon, double whenever you would do so in a money game. But you must also double whenever you have the advantage, if there is a chance that Black may not be in a position to accept next time.
It is important to note that Black should not accept the double more readily at this score than in a single game. In fact, he needs a somewhat higher chance of winning than one in four to justify taking the double. This is because if he refuses, he still has a chance of winning two games running, and the added possibility of winning the first game with a gammon gives him better than one chance in four of winning the match.
In the given scenario, White has a double in a game where he needs 2 points to win and the score is tied at 13-all in a match to 15. If White doubles, he has a 26 out of 36 chance of bearing off both his men, and in the 10 cases where he fails to do so, Black wins 17 out of 18 times (except when he throws a 2-1). If Black accepts the double, he will win just over 26 times out of 100 on average, which would make it a profitable move in a money game. However, in a match, Black should refuse the double as there is a chance of winning a gammon on the next game, in addition to the chance of winning two games in a row, which gives him a better chance than 26 out of 100. Moreover, the fact that White will have to play carefully to avoid losing a gammon will lead him to alter his play, thus reducing his chance of winning the game.
If you have a chance of a gammon, you should not let that prevent you from doubling unless it is a very solid chance. It is still valuable to get the cube to 2 or to get your opponent to concede the game if you can. However, you should avoid giving very early doubles, where a good part of the reason for doubling in a money game would be the chance of a gammon.
In the given scenario, White has a good chance of winning if Black accepts the double, but since it is a match play, Black should refuse the double. This is because if Black wins the next game, he will have a better chance of winning the match by getting a gammon or by winning two games in succession.
It is important to note that in a match play, one should be careful about doubling when they have a good lead and are close to victory. For instance, if White leads 13-11 in a match up to 15, it is better to play for a gammon rather than to double. This is because if Black accepts and wins, he will immediately redouble to 4 and play the game for the match. Winning 4 points instead of 2 won’t benefit White at all, but losing 4 will cost White the match. Similarly, if the score is 11-7 in a match up to 15 and the game could be a gammon either way, one should have a considerable advantage to justify doubling. If Black accepts and White loses a gammon, White will lose the match with it.