Position 376

 How should White play 32 here: 

This is the position sent to me by Greg Ash. Greg suggested that I use it in the positions of the week, and I agreed and put it in the queue. On Wednesday last week it went to the top of the queue, as I learnt that Greg passed away. He was the past president of the Australian New Zealand backgammon Federation, and gave generously of his time for the promotion and benefit of backgammon. So, in honour of Greg, this position has moved to the top of the queue. You will be missed Greg.

White is in the race to get all his checkers off before Black does, so considers playing 3/off 2/off:

In order to compare the alternatives, we have to have some common currency to measure how good each alternative is. I would count the number of crossovers for either side for each alternative. It may not be the best alternative, but it works and is easy.

A crossover is moving from one quadrant of your board to another, or entering from the bar, or bearing off one checker. For Black here, you need 3 crossovers to get your black checker into your home board and then another crossover to bear off. That is a total of 4 crossovers.

For White who is now bearing off, each crossover is considered to be taking two checkers off. Here you would need 3.5 crossovers to take off all your checkers. You would round this up to 4 crossovers.

So, this alternative leaves you in a 4 versus 4 crossovers, with black having the advantage as Black will be on roll.

Also Black has the advantage here because with 11 rolls they will hit you with a 2.

Consider 6/3 2/off:

Black has the same 4 crossovers, and as White has 8 checkers to bear off, you too need 4 crossovers to bear off all your checkers.

This alternative has to be better than the previous one, because although you still have 4 versus 4 crossovers, Black has no rolls that hit one of your checkers.

Consider 6/4*/1:

Now Black needs one crossover to enter, then 3 crossovers to get their checker into their home board, and one more crossover to bear off, which is a total of 5 crossovers. One more than the previous alternatives.

You need 4.5 crossovers, which we round up to 5 crossovers. But the big difference is with 16 rolls Black will stay on the bar, and even if you only take off one checker, you will be down to 4 crossovers, which is an improvement.

Even moving from a 4 versus 4 crossovers situation to a 5 versus 5 crossovers position gives you more time to roll doubles.

It can be very discouraging to be the underdog, but here finding the correct play gives you 10% more winning chances, so it is worth taking the time to evaluate the alternatives. As a friend once said to me “there is no glory finishing the match with 11 minutes left in your time bank, if you could have made better decisions”.





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