Master's Panel 4—Updated
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From Backgammon Times, Volume 3, Number 3, Fall 1983.
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Mike Senkiewicz recently discovered some old issues of Backgammon News, a newsletter published by Prince Alexis Obolensky's World Backgammon Club in the early 1970s. In each issue Obolensky ran a Master's Panel where several leading players tackled a series of interesting problems.
With Backgammon News Editor Joe Pasternack's permission, we have reprinted a set of Master's Panel problems along with the answers of the old Masters. To make things interesting we have put the problems to a panel of current Masters hand-picked by Senkiewicz.
This is the fourth in the series. See how you handle the positions and see if the Masters agree.
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Problem 1
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Position 1.
How should Black play 5-2?
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Old Masters (Circa 1974)
| Ralph Chafetz |
8/3, 13/11 |
| Mr. and Mrs. John Crawford |
6/1*, 3/1 |
| Tim Holland |
8/3, 24/22 |
| Paul Magriel |
8/3, 13/11 |
| Prince Alexis Obolensky |
8/3, 24/22 |
| Tobias Stone |
8/3, 13/11 |
| Stan Tomchin |
8/3, 24/22 |
New Masters
| Kit Woosley |
8/3, 13/11. Making the ace-point would leave Black with a very inflexible position which would be difficult to improve. For the two, 13/11 is better than 24/22 because the men on the 24 point are not yet hemmed in. The split runs the very real danger of getting a couple of men stuck on the bar while the prime is not yet complete. |
| Kent Goulding |
8/3, 13/11. 8/3, 24/22 is second choice. Pointing on the ace point is weak. |
| Malcolm Davis |
6/1*, 3/1. Tough play; any other choice must include 8/3. |
| Bill Robertie |
8/3, 13/11. 6/1*, 3/1 is a hopeless play. Playing the 5 to the 3-point is clear. Despite the duplication of ones, I would play 13/11 with my 2. Having a third checker hit would remove Black's excess timing and could result in a quick squeeze. I would guard against that possibility first and count on getting my back men out later. |
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Problem 2
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Position 2.
How should Black play 3-1?
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Old Masters
| Ralph Chafetz |
4/3*/off |
| Mr. and Mrs. John Crawford |
6/3*/2 |
| Tim Holland |
4/3*/off |
| Paul Magriel |
4/3*/off |
| Prince Alexis Obolensky |
6/3*/2 |
| Tobias Stone |
4/3*/off |
| Stan Tomchin |
6/3*/2 |
New Masters
| Kit Woosley |
4/3*/off. It would be very wrong to volunteer a shot with 6/3*/2, for even if you get away with it you are far from home (my computer runs show that against the ace-point game this play is 15% more likely to result in getting hit). The only reasonable alternative is clearing the 5-point. This is a bit safer vs. the ace point than my play, and minimizes the risk of leaving two blots. However, my play knocks White off the 3-point, and this is the deciding factor. If White were not on the 3-point, clearing the 5-point would be clearly best. |
| Kent Goulding |
4/3*/off. I don't care for 6/3*/2. My second choice would be 5/4, 5/2. |
| Malcolm Davis |
4/3*/off. |
| Bill Robertie |
4/3*/off. This is not much of a problem. 6/3*/2 (which, frankly, would never have occurred to me) immediately must be rejected since it leaves a blot this turn, and is just as likely to leave a blot next turn as the safe play. The other safe play, 5/4, 5/2, is much more likely to leave a shot on the second turn as 4/3*/off. |
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Problem 3
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Position 3.
How should White play 6-1?
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Old Masters
| Ralph Chafetz |
23/17, 13/12* |
| Mr. and Mrs. John Crawford |
24/23, 8/2* |
| Tim Holland |
23/17, 13/12* |
| Paul Magriel |
23/17, 13/12* |
| Prince Alexis Obolensky |
8/2*, 3/2 |
| Tobias Stone |
24/23, 8/2* |
| Stan Tomchin |
23/17, 13/12* |
New Masters
| Kit Woosley |
23/17, 13/12*. My idea is to take control of the outfield, giving White as much maneuvering room as possible and trying to force Black to crunch as soon as he enters. This is a fascinating position, for there are several reasonable plays, any of which may be substantially better or worse than the others, and we really don't know. |
| Kent Goulding |
23/17, 13/12*. |
| Malcolm Davis |
23/16*. Must make strongest play, 23/17 essential. |
| Bill Robertie |
23/17, 13/12*. What a position! White has at least 7 plausible plays. Since White desperately needs freedom to maneuver, my choice is 23/17, 13/12*. |
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Problem 4
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Position 4.
How should White play 4-3?
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Old Masters
| Ralph Chafetz |
21/17*/14 |
| Mr. and Mrs. John Crawford |
24/21, 13/9 |
| Tim Holland |
21/17*, 7/4 |
| Paul Magriel |
24/17* |
| Prince Alexis Obolensky |
24/17* |
| Tobias Stone |
24/17* |
| Stan Tomchin |
24/17* |
New Masters
| Kit Woosley |
21/17*, 7/4*. Risky, but there are only 14 return hits, and White stands to make big gains by claiming his 4-point if he gets away with it. Even if he gets hit, White will still have one roll to recover. The more conservative plays also leave some return shots, and result in positions which are very difficult to improve. |
| Kent Goulding |
21/17*/14. Hitting is a must, following which bringing an extra builder to bear on the 8 and 9 points while at the same time getting off of 5's looks best. |
| Malcolm Davis |
24/17*. No other play. |
| Bill Robertie |
21/17*/14. 21/17* is clear. White then has 4 reasonable 3s. 7/4* is too risky. White's game disintegrates if Black comes back with a 4 or 3-3, 2-2, or 1-1. There seems to be no necessity for 24/21, since Black has no threats to contain that checker. 13/10 is too loose. I like 17/14 since it takes away 5's from Black and at the same time creates a builder for the 8 and 9 points. |
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Problem 5
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Position 5.
White doubles.
Should Black take?
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Old Masters
| Ralph Chafetz |
yes |
| Mr. and Mrs. John Crawford |
money yes, tournament no |
| Tim Holland |
yes |
| Paul Magriel |
yes |
| Prince Alexis Obolensky |
yes |
| Tobias Stone |
yes |
| Stan Tomchin |
yes |
New Masters
| Kit Woosley |
Trivial take. To see this, we know that with a flush position, 5 men off is just barely a take against a closed board. Black figures to miss on average about once due to the gap, so this is roughly equivalent to a flush position with 6 men off. In fact, White should not have doubled. There are very few market losing sequences, while if White rolls something awkward, such as 4-4, he will wish he hadn't upped the stakes. |
| Kent Goulding |
Take. White certainly has a big advantage but Black will be taking next turn too. I doubt that it is correct to double in the first place. |
| Malcolm Davis |
Yes. Clear. |
| Bill Robertie |
Take. This is a technical position which is well understood. Since Black has 7 men off, White's double is not correct. Although he is a favorite, White should wait until he has borne off 2 men before doubling. (Black would still have a take at that point.)
Crawford's comment that this is a take for money but not in a tournament shows the murky state of tournament strategy as recently as 9 years ago. For an initial double, there is essentially no difference in taking strategy between money and tournament play. |
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Problem 6
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Position 6.
White doubles.
Should Black take?
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Old Masters
| Ralph Chafetz |
no |
| Mr. and Mrs. John Crawford |
no |
| Tim Holland |
no |
| Paul Magriel |
yes |
| Prince Alexis Obolensky |
yes |
| Tobias Stone |
yes |
| Stan Tomchin |
yes |
New Masters
| Kit Woosley |
We've got the prime, but he's got the time. There are several ways for Black to win the game. He might jump out and win the priming battle; he might attack White's blot and scramble everybody up and over while White is on the bar; he might make an advanced anchor and win the race; or he might get a shot from some anchor and luck out a win even with a crunched board. Furthermore, he will usually get an anchor higher than the ace-point, so the gammon threat is not overly serious. Each of these possibilities is small, but the total is likely to get over the 25% mark. The results of my rollouts were inconclusive. It wouldn't shock me if it were a pass, but I know that I would take at the table. |
| Kent Goulding |
Take. However, this is close. |
| Malcolm Davis |
Yes. An easy take in Texas. |
| Bill Robertie |
Take. This requires some explanation. My simulation indicated that Black has a very close pass, although the margin for error was such that it might be a narrow take. White, however, needs to know how to play the position. In particular, he needs to hit Black off the 4-point if he doesn't throw a number that closes the 4-point directly. With a 2-1, for instance, his best play is 7/4*. White needs to hit because Black would have reasonable chances in the race if he can make the 4-point.
Against a weak or unknown opponent, therefore, Black should take, since he can't be sure White would play properly. Against an excellent opponent, Black should pass. |
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Problem 7
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Position 7.
How should Black play 3-1?
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Old Masters
| Ralph Chafetz |
8/5, 6/5 |
| Mr. and Mrs. John Crawford |
8/5, 6/5 |
| Tim Holland |
24/21, 8/7* |
| Paul Magriel |
24/21, 8/7* |
| Prince Alexis Obolensky |
8/5, 6/5 |
| Tobias Stone |
8/5, 6/5 |
| Stan Tomchin |
8/5, 6/5 |
New Masters
| Kit Woosley |
8/5, 6/5. At least White can't both make an inner board point and safety his blot on his next roll, so the simple play should put Black in good shape. The tempo gain and the 6 duplication make 8/7*, 24/21 attractive, but leaving both stacks of five men is a bit too inflexible for me. This is largely a matter of style—it is certainly is no big deal. |
| Kent Goulding |
8/5, 6/5. While hitting is often wrong, it is actually quite close in this position. |
| Malcolm Davis |
8/7*, 24/21. |
| Bill Robertie |
8/5, 6/5. Since White can't both make the bar and an inner point on his side at the same time, this play rates to keep the initiative. |
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