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| Magriel's NYT Columns |
In some backgammon positions multiple possibilities arise. When analyzing these positions, you must first formulate your best overall strategy, then determine the best tactical play accordingly.
This is particularly true in positions such as the diagrammed one, in which there is a “battle of primes,” that is, when both sides are blockading each other. Black has two men on the 23-point behind White’s 5-point prime. Meanwhile, Black has his own broken 5-point prime, behind which White has a man trapped on the 1-point.
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| Black to play 6-4. |
When Black rolled a 6-4, he had several immediate choices, each of which reflected a different game plan:
- He could simply run with one back man by playing 23/13.
- Another possibility was for him to attack by playing 7/1*, 5/1.
- He could run-and-attack by playing 23/17, 5/1*.
All of these choices, while having desirable features, have serious drawbacks.
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23/13 |
7/1*, 5/1 |
23/17, 5/1* |
Similarly, the run-and-attack scheme was potentially even more dangerous — Black would now be playing with four blots (exposed men). In both these cases, Black stood a significant chance of not only losing the game, but of being closed out and gammoned. In the actual tournament situation, because of match-score considerations, Black was particularly reluctant to risk losing a double game (gammon).
Black’s other choice, attacking White and making his 1-point, also had liabilities. If White reentered with a 4, Black would probably lose. More importantly, by not running out with a 6, Black left both back men still trapped behind White’s prime.
Black did not choose any of those three plays — but ingeniously found another approach altogether. He made a waiting move, 9/3, 6/2 and so forced White to move.
Of course, White might escape with 3-4, 3-5, or 3-6; but if White fails to escape, it is likely that he will be forced to break his valuable 5-point prime. If White is allowed to continue moving forward he will be in danger of totally destroying his position. Indeed, 6-5 and 5-4 are immediately “disaster” rolls for White, compelling him to leave a double direct shot.
Black’s game plan of waiting, although passive, was also effective: It gave Black significant winning chances without the danger of being closed out and gammoned.
Rollout
![]() Tom Keith 2013 |
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Money play Black owns 2-cube Black rolls 6-4 1296 games with VR Checker play: 2-ply Cube play: 3-ply Red |
| 6-4: | Game | G | BG | Equity | ||||
| 1 | 9/3, 6/2 |
W L |
.4222 .5778 |
.0594 .0793 |
.0024 .0020 | −0.0272 |
| Wait |
| 2 | 23/17, 9/5 |
W L |
.4151 .5849 |
.0578 .1295 |
.0020 .0017 | −0.1040 | (0.0768) | |
| 3 | 23/13 |
W L |
.4413 .5587 |
.0632 .2154 |
.0022 .0051 | −0.1130 | (0.0858) | Run |
| 4 | 7/1*, 5/1 |
W L |
.3581 .6419 |
.0182 .1236 |
.0003 .0040 | −0.2705 | (0.2433) | Attack |
| 5 | 23/17, 6/2 |
W L |
.3909 .6091 |
.0545 .2390 |
.0020 .0057 | −0.2757 | (0.2485) | |
| 6 | 23/17, 5/1* |
W L |
.4076 .5924 |
.0448 .2772 |
.0013 .0135 | −0.2780 | (0.2508) | Run+Attack |
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