Doubling Cube in a Match Game

The backgammon position below came up in my first round match in a major backgammon tournament in Florida at the end of August. I was playing one of the top players in the world, Richard Muniz, and I was Black, holding a 2 cube, and I was losing 3-6 in a match to 11.  

I have several questions for you to consider regarding this position, and I believe that if you take the time to consider all the answers carefully, you will gain some real insight into the use of the doubling cube. 

Question 1: Should Black redouble at this score, losing 3-6 to 11?

Question 2: If Black redoubles, should White take?

Question 3: If the score was reversed, and Black was winning 6-3, should he redouble?

Question 4: If this was a money game, what is the proper cube action for both players?

I hope you have given a lot of thought to your answers, and I congratulate you if you got them all correct. 

First, let’s look at what Snowie says is likely to happen to this game. (Snowie is a backgammon software program that gives you the likely odds of wins, losses and gammons for any position, and it is generally very accurate.)

What the above says is that Black will win this game about 80 percent of the time and White will win about 20 percent of the time.  But it also says that most of Black’s wins will be gammons (48.6 percent). 

Over the board, a player’s first job is to try to guess at these numbers, but when that is done, only half of the job is complete.  Once you estimate these numbers, you must then decide whether or not it is right to double (or redouble) at the current score, and whether it is right to take at that score. 

So let’s get to the specific answers to the questions I posed at the beginning of this article. 

1. Should Black redouble, losing 3-6?  The answer is clearly no.  At this score, you want to play on because you have such a good chance to win 4 points.  If you double, you will only win 2 points, because any reasonable player who understands this position would drop the cube.
2. Should White take if Black redoubled?  Of course not.  You are winning the match and if you drop you lose 2 points, but if you take, you lose 4 points 80 percent of the time, and many times you lose 8 points by getting gammoned.  So you are happy to get out of this game losing 2 points if your opponent makes the “mistake” of redoubling here.
3. If the score were revered and Black was winning 6-3, again you would not want to redouble because by playing on you have little to lose…you lose the game only 20 percent of the time, but you win so many gammons you should play on.  But there is another major factor here—you lose 20 percent only if you play the game on to the end.  Holding the cube actually gives you the leverage to end the game just about whenever you want.  Let’s say your position gets worse and it no longer looks like you will win a lot of gammons.  You might still be in a strong enough position that will allow you to redouble and get a pass.  So holding the cube has great power.
4. In a money game, it would be a major mistake to redouble, and of course, if Black made that mistake, White should simply drop.  Any time you can win gammons twice as often as you might lose the game, it’s worth playing on without redoubling.  Again, if things get a little worse for Black, he still holds the cube and can end the game with the cube.

Far too many players don’t consider gammon risks when they give or take cubes, and these risks must be factored in to every cube decision. 

By the way, in the match against Richard, I was fortunate enough to win and make it to the semi-finals of the tournament before losing at Double Match Point to another very fine player. The tournament was won by Michael Corbett, a Giant of Backgammon.