Doubling guidance - Backgammon double
In the running game, you should double when:
- You appear to be 2 or 3 turns ahead.
- Your pip point count is 8% to 10% ahead.
You accept a running game doubled when you are not more than 15% behind.
In middle-game: middle-game doubles are always for positional reasons, so to double in mid-game you need:
- A strong block of 4 to 5 consecutive points;
- 2 or 3 of your opponent's men behind your block;
- Your opponent with a weaker block and/or unlikely to be able to trap your men behind it.
Middle-game doubles require considerable judgement and experience, and there is no easy formula for acceptance or refusal. All positional games can be reversed with luck and skill. Therefore take care not to double too early, your advantage may vanish quickly.
In the back game: if your opponent is playing a back game the chances are that you will be forced to expose a man at some stage of the bearing off process. Therefore you should not double a back game until either his board is breaking up, or until he is forced to weaken his back game by giving up control of one of the two points he holds in your home board. The moment you see his position weakening, double him.
In the end game. Double when:
- The distribution of the men in the home boards is in your favour, i.e. if your men are placed on the lower points, whereas his are placed predominantly on the higher points, and particularly if he has a gap in the middle. He will very probably throw the number relating to that gap at some stage, and will have to move instead of taking off one man. Therefore you can value each gap in your opponent's home board as being the equivalent of a lead of one additional man off the board.
- If positional factors are equal, and you both have the same number of men, the advantage will be with the person whose turn it is to throw the dice. He will be two men ahead after his turn, and (excepting doubles) will almost certainly stay that way. Therefore if you are in this position you double him to force his resignation. There is no point in allowing play to continue, as he might throw a double and catch up with you. If this is done to you, refuse the double.
- In the last 1 or 2 throws of the dice double if your chances of getting off before your opponent are better than 50%. If this is done to you accept if his chances of winning are not more than 74%.
Potential gammon and backgammon situations; where it is likely that you will gammon or backgammon your opponent, do not double. Your double gives him the option to refuse and concede one point to you. Force him to play to the end and win a 2- or 3-point game for the gammon and backgammon respectively.