Optional Rules

The following optional rules are in widespread use.

Automatic doubles. If identical numbers are thrown on the first roll, the stakes are doubled. The doubling cube is turned to 2 and remains in the middle. Players usually agree to limit the number of automatic doubles to one per game.

Beavers. When a player is doubled, he may immediately redouble (beaver) while retaining possession of the cube. The original doubler has the option of accepting or refusing as with a normal double.

The Jacoby Rule. Gammons and backgammons count only as a single game if neither player has offered a double during the course of the game. This rule speeds up play by eliminating situations where a player avoids doubling so he can play on for a gammon.

Crawford Rule. The Crawford rule is named after John R. Crawford. When either of the players is just short of one point from the victory, then the opponent cannot announce a double in the subsequent game. This particular game, where double is prohibited, is called the Crawford game. Scientifically, even if a double is announced and accepted by the player approaching the victory, it will be nullified because point 1 or 2 can create hardly any difference for him. Rather the double may benefit the opponent who is losing. But if the Crawford game remains indecisive in terms of final win or loss, then all the rules of double and redouble will be back in place in the subsequent games. This rule has been accepted worldwide. Even United States Backgammon Tournament Rules & Procedures follow Crawford rule at the closing stage of any tournament.

Holland Rule. It is an extension of Crawford rule where the rule says that after the Crawford game, the trailer can announce a double after completion of two valid rolls of both the players. But Holland rule could not sustain in the long run because of its confusing nature and complexity in implementationJacoby Rules and Crawford Rules are followed even in the online games today. But the online competitors declare their special terms and conditions (if any) in their site very clearly for the convenience of the players, because you may find many players from different parts of the world are playing simultaneously in the same game.