Problem of the Week #153: October 21


Cash game, Black owns the cube.




Black to play 6-1.


Something a little different. Find 6 candidate plays. Arrange them in order from best to worst. Discuss.


Note: All ‘cash game’ problems assume the Jacoby Rule is in effect. That is, you can’t win a gammon unless the cube has been turned.

Leaving the 21point is unwise, making the one point is outside the objective of priming with a backgame, 13/6 could be an option, but best to me seems to be 13/7 13/12. When the point is made, it could be a huge problem with that gap for white. If white hits it's no huge disaster with a broken three point board.

21/15* 15/14
21/15* 13/12
13/7 8/7
13/7 5/4
13/6
8/2* 2/1

Your timing is questionable for a backgame, the man on the 1 is misplaced, and you have a split 3-prime to work with. Yippee. Seems like there are two reasonable ways to play this, coming forward immediately or playing it as a backgame, working on structure now and trying to hit when you're in better position to contain.

8/2*/1 just seems like completely the wrong idea because that's 2 dead checkers and closing the 1 doesn't accomplish anything now.

13/7 8/7 wouldn't be a bad idea if his stray checker were on the 1, but making his 6s into productive rolls doesn't seem so smart.

21/15* 15/14 and 21/15* 13/12 13/12 should be better because you get more combos to make another useful blocking point. Also, this line of play gives you a chance to quickly recycle the useless man on the 1.

13/7 5/4 either gets you some timing or very likely gets you another useful point. Either way, it seems ok.

13/6 doesn't really do anything major. Just puts a guy on a reasonable building spot for a slightly more forward intended prime, but also doesn't expose anything.

The first two are bad, 8/2/1 probably being worst. 21/15*/14 seems like a relative mistake so call it 4th. The other 3.. bleh. All of them seem reasonable to me.

Go forward/backgame/blitz in that order

1. 21/15*,14
2. 21/15* 13/12
3. 13/7, 5/4
4. 13/7,13/12
5. 8/2*, 5/4
6. 8/2*,1

This may be a position, where the game of backgommon can be discussed in a nutshell. First of all, what is your game plan? There are several types of direction for playing your game: race, holding game, priming game, blitzing game, backgames, deep anchor games. And backgammon is like life, if you’ve got lemons, you have to make lemonade. In my toolkit there will be also the general principles: efficiency, non-commitment, connectivity and robustness. A move, which will address most of them, not violating one ore more of them, must be in the driver seat.


Black has four men back, white one. The race is 173:108. Black is trailing by a whopping 65 points. Both armies are not connected. White has a straggler on the two point. Black holds the ace- and fourpoint in the opponent home board. White has managed to build a solid fourpoint block in front of blacks points. But three spares are already in brittle position and the fourth can be hit and send back to the start. White has also lost the midpoint, whereas Black is present all over the board. By now, White has 14 men in the zone and Black 8 men.

Efficiency. White has problems with his brittle spares. A man can be sent back, a straggler has to come home. This is also committend. There is no choice, this men must go to the main body of the troops. There is no time to hold a fort. Black has two liabilities: the man one the acepoint and the brittle spare on five.

Non-commitment. White is doomed to defend against the possible backgame and getting the army united (the people united can never be defeated). Despite Black is behind 65 pips in the race, there are several doors open. He can hit and turn the game in a forward one. He can build on his polish prime, staying pure for the backgame. He can start a blitz. At least, he can temporize.

Connectivity. Both participants have problems in this field. Every attempt of Black, to turn into a forward game is hampered by a ton of men behind, almost a third of his troops. But he has the midpoint. White has the main body of his army well connected. But one man has to ride through the canyon, one man can be sent back. There is no fort in the outfield.

Robustness. 65 pips is a lot. But for a backgame, it is the start of robustness. White has problems. There are clouds in the horizon. His spares are brittle, the enemy is on the edge and perhaps two men are doomed to ride through the canyon, despite the snipers on the hill.

So what is your gameplan?

The blitz, 8/2* 2/1 can be discarded. Only 8 men in the zone with no quick reinforcement against a good frontposition, is doomed to death.
What about hitting in the outfield, going forward? In the opening, we are often try to complicate, if one man has escaped, to send a second man back, because one man back is a huge asset. One lucky move, and the loner will be away and the race will be even more against us. But we are paying a huge price, shooting from an asset. We are also activating the brittle spares of the block in front of us. Soon the men in thin air could be totally disconnected. Two ways to play the ace then. Shy with 15/14, leaving the man on a random place, or playing 13/12, diversifying the snipers on the hill.

At DMP, I will be in time machine, playing ultra-pure. 13/7 5/4 is a hot candidate. Eat or die! Another pure attempt is 13/7 13/12. 13/7 8/7 goes also in this direction.

As Mr. Robertie wrote in “Modern Backgammon”, we humans love black or white. Barack Obama or Mitt Romney. Drinking or AA. Grey isn’t our color. But even in an apparently well defined position, we can find a move, that holds the doors open. The constructivist Heinz von Foerster once said: “Act always in a manner, that will grow up your possibilities.”

What about 13/6? Not decisively. But a lot of upsides. Adds a man to the zone, on place where we want to have a spare. Burns not the bridges to a forward game, but doesn’t hurt the backgame. Brings the dilly builder on five in a better mood with a compagnon and even the structural weakness on the guff. It is a quit move, because it slams no door. Non-commitment will be my driver seat for a doubled cash game. OtB it is perhaps not to find, but with QF, standing on the shoulders of a giant, it isn’t impossible.

So my candidate list is:

13/6
13/7 5/4
13/12 13/7
13/8 13/7
21/15* 13/12
21/15* 15/14
8/2* 2/1

Play A. Blitzing (8/2*/1) must be wrong. No way you can attack and escape at the same time. This seems like the worst play conceptually, though I am not sure it I worst.

Play B and C. I also don’t like any play with 21/15*, say You may regret leaving that 4 anchor – especially if White enters and hits you loose and miss – which happens a decent amount of the time. These plays may be worse than blitzing if you get gammoned too much (ie when you lose the battle for the 4-point) and get a lot of guys piled up on the ace point). 21/15*, 13/12 is a bit better if you survive and 21/15*, 15/14 if you don’t.

Play D the wimpy 13/6 can be dismissed since it does nothing.

Play E making the bar 13/7,8/7 is also ridiculous. You can’t prime here and giving sixes to escape for free can’t be right.

The rest of the plays are pure backgame plays. For my money, any of these are at least the right idea. I like the risk/reward of the last two plays (G and H) the best. Holding the ace and four anchors keeps the downside limited. If you get hit you get more timing and if you don’t get hit you hold out some hope of wining going forward by organizing an offense quickly. I think it is also important to note that White already has the deuce point – which is not ideal for him. Another angle to consider is that 1-4 isn’t the best backgame. By slotting the key points you might luck out and make it 1-3-4 game or possibly upgrade to a 1-3 game.

Play F is the kamikaze 8/2*, 5/4. This has some merit since you would love for White to hit you on the ace and recycle that guy – but what if White doesn’t hit? Black’s timing is a bit iffy but I don’t we are desperate enough where the kamikaze play is called for. I don’t like this one.

Play G puts em where you want ‘em 13/7, 13/12, by trying to make the bar.

Play H also puts ‘em where you want ‘em 13/7, 5/4. This tries to make the best use out of all your checkers and I like it a bit better than play G.

FWIW, my rankings are A to G (worst to best). Anxious to see the answers.

Black has a limited number of ways in which to play a 6: 8/2*, 13/7 and 21/15* are the only possibilities when he moves the 6 first. By playing the 1 first, Black can also move 13/12/6 or 8/7/1. Of this latter pair, 13/12/6 can be ignored because it transposes with 13/7/6 (which I will consider). The other, 8/7/1, does not transpose. That’s because playing the 6 first hits, 8/2*/1, while 8/7/1 does not.

To simplify the discussion below, I have assigned a letter to each candidate play. Although I could have used A, B, C, and so on, I have chosen an arbitrary combination of upper and lower case letters, even throwing in some italics. A, B, C, etc. might just as easily been used.

Black Plays 21/15*

Play E: 21/15*, 5/4
Play B: 21/15*, 8/7
Play S: 21/15*, 13/12
Play R: 21/15*, 15/14

One of the most important decisions for Black is whether to play this position as a backgame. No matter what he decides, however, hitting from the 21pt is a very dubious plan. Without the 21pt, Black loses the chance to play a backgame (for the moment), and even when Black decides he does not want to play a backgame, he gives White three numbers (1, 3 and 4) to hit back with. So long as Black has two checkers stranded on the 24pt, he should hold onto the 21pt so that they remain connected to his outfield forces. Hitting from the 21pt, therefore, ranks at the bottom of Black’s choices. Having said that, of the plays enumerated above, Play R is probably the best. It minimizes the number of blots at a time when White is sure to be attacking. Second best is S, which avoids slotting in front of White’s rear checker.

Black Plays 8/2*

Play A: 8/2*, 2/1
Play a: 8/2*, 5/4
Play o: 8/2*, 8/7 (italic)
Play O: 8/2*, 13/12 (italic)

When Black chooses to hit on the 2pt, he may think he is playing some version of the hari-kari maneuver. The 2pt is a bit too deep, however, for that plan. If Black wants to be hit, the best way to accomplish that is by playing down to the bar point with the 6. Should Black elect to hit on the 2pt, then slotting the 4pt (Play a) is the best way to commit suicide.

Another possibility is to hit on the 2pt, and then continue on by making the 1pt (Play A). This play launches an attack, but it’s a feeble one that almost certainly cannot succeed. With only 8 checkers in the zone, Black doesn’t have enough ammunition to follow it up. At the same time, making the 1pt is awkward in case Black is forced later to switch into a backgame. Nevertheless, I like this play better than leaving a blot on the 2pt.

All the plays in this group are weak. The only reason they don’t rank below hitting on the 15pt is because they do not strand the rear checkers. Other than that, they are not a whole lot better.

Black Plays 7/1

Play o: 8/7, 7/1

Making the 1pt without hitting is even worse than making it after a hit.

Black Plays 13/7

Play N: 13/7, 5/4
Play O: 13/7, 7/6
Play D: 13/7, 8/7
Play d: 13/7, 13/12

The pip count is Black 173, White 108. Black trails by 65 pips, a bit too low for most backgames. His best option is to adopt a two-way game plan. He can aggressively slot, and be prepared to go forward when he is missed. When he is hit, he can play a backgame, and have better timing than he has now.

To this end, slotting the bar point is clearly Black’s best 6. Lifting the blot up to the 6pt (Play O), should not even cross Black’s mind for an instant. Should he cover (Play D)? I think not. By blocking White’s rolls of 63, 64 and 66, Black may be able to force White to abandon his 8pt.

That leaves just two choices. Black can try the double slot (Play N), or else he can diversify his outfield builders (Play d). I think these are the two best ways to play this 61. I have a slight preference for Play d, because it gives somewhat better chances to complete the 4-point block when White cannot hit, and also gives better outfield coverage when White escapes.

My Solutions

Ranked from best to worst, here are my top 6 solutions:

Play d: 13/7, 13/12
Play N: 13/7, 5/4
Play D: 13/7, 8/7
Play O: 13/7, 7/6
Play A: 8/2*, 2/1
Play a: 8/2*, 5/4

For the Record
I am so often wrong that I like to post my record in these messages. It's kind of a truth-in-advertising thing. Grunch: I have been answering these problems without the use of a bot, and before checking the excellent solutions of others, since Problem 28. My record at this writing is 54%.

candidates:

21x15/14 the hit and outfield control variation
21x15 13/12 the hit and barpointcontrol variation
8x2/1 the blitz-variation
13/6 the wait for a better opportunity variation
13/7 8/7 the priming variation
8x2 5/4 the super-timing variation
13/7 5/4 the pure-play variation

Black is in a 4-1 backgame-situation right now. The timing seems quite allright 173-108.
That's a 65 pip-difference, enough for a 4-1 backgame i think. A little more is allright, but not too much more.

Second question: Is blacks board ready for a hit? I usually like to have my golden structure complete before I hit.
Ok then, will i get another chance?
Yes I think so, not only because of the last white checker, but also because white's 6- and 8-point are stripped.

Best to worst:

1. 13/7 8/7 gives a pure structure, lets white play the 6's for timing sake (D6 certainly wouldn't hurt).
And if white doesn't hit: a 5 makes a prime and might cause some front-cracking.

2. 13/6 a kind of waiting move, brings another builder.

3. 21x15 13/12 the best of the two hit-variations, since it bears an extra builder on the bar-point.

4. 21x15/14 the other hitter

5. 13/7 5/4 strategically sound, but has the disadvantage of creating overtiming and possibly too much time on the bar,
black might not have enough time then to make the golden structure.

6. 8x2 5/4 this sort of moves is only necessary when your short on timing, the checker on the 2-point is somewhat out-of-play,
along with the checker on the ace, it's certainly too much.

7. 8x2/1 the blitz, and making the ace-point is most certainly not the strategy to pursue here, it takes away the opportunity too, if necessary,
pick up a second checker when the hit comes late.

I finally decided to read the excellent discussions here without putting the effort to rank several plays (not enough time lately). Just wanna say that over the board and even as a quiz (and before reading all the discussions), I would have played 13/6. After reading the discussions, I really doubt it's best, but I'm still anxious to read the answer posted by Mr. Bill Robertie to see if it can at least stand on the podium.

So there I go...