Position # 14

[PersianLord]

Score :         Red 0-0 White
Pip-counts :  Red 116-124 White
Match :        9-point



Position ID: NjeDARRjO4kDBA, Match ID: UYklAQAAAAAA

First make your choice and then read on.

Spoiler

It's true that red can make his 7-point with 10/7-8/7 and increases his chances of containing white's back men for a bit longer, but the right move is playing agressively by 6/3*/2* as GNUBG clarifies clearly :

   1. Cubeful 2-ply    6/3*/2*                     MWC : 58.08%  Eq.:  +0.746
       0.659 0.388 0.009 - 0.341 0.152 0.011
       
    2. Cubeful 2-ply    10/7 8/7                     MWC :53.99%    Eq.:  +0.368 ( -0.377)
       0.543 0.234 0.013 - 0.457 0.155 0.004
       
    3. Cubeful 2-ply    6/3* 4/3                     MWC : 52.28%   Eq.:  +0.210 ( -0.536)
       0.536 0.256 0.008 - 0.464 0.252 0.025
     
    4. Cubeful 2-ply    8/7 6/3*                     MWC : 51.95%   Eq.:  +0.180 ( -0.565)
       0.522 0.254 0.008 - 0.478 0.266 0.025

    5. Cubeful 2-ply    10/9 6/3*                    MWC : 51.91%   Eq.:  +0.176 ( -0.570)
       0.526 0.264 0.009 - 0.474 0.269 0.026
     
As can be seen, playing safe with 10/7-8/7 is actually a bad blunder as it is equal to an equity loss of 0.377 and MWC loss of 4.09%. The reason is that with playing safe, red will have an incomplete 4-point prime in front of white's back men and he will never be able to build a full prime as he already has burried 2 checkers in the ace-point and is now short of amunition. Also note that white can build an annoying anchor with an ace and make the situation worse for red, as red has an alone back man who is threatened to be contained later.

By playing 6/3*/2*, red increases his chances of a gammon win to a whopping 38.8%, compared to just 23.4% for 10/7-8/7 and with the cube on 2, he will be the clear favorite to win the match. Consulting our "probability table" that I had posted some weeks ago, we realize that white's chance to land safely both of his hit checkers on the next roll in the red's 4-point board is just 11% ! Thus, red may not fear of a return shot and even if so, he will have 56% of chance to land and even make a much-needed anchor in white's board. Therefore this is a golden opportunity for red to follow an agressive strategy in order to inflict a heavy damage to white's game plans. Alas the timid players will miss these chances more than often!

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