Annotated Game |
My partner was Donald Kahn. Our quarterfinal match against Leo Fernandez and Jose Salema started badly. One game in particular was responsible. We were trailing 4–5 in the 19-point match.
Woolsey-Kahn (Black) | Fernandez-Salema (White) |
1. | 5-4: 24/20, 13/8 | 5-2: 24/22, 13/8 |
2. | 6-1: 13/7, 8/7 |
| White to play 5-1. |
2. | . . . | 5-1: 13/8, 6/5* |
Running with 22/16 is possible. This duplicates our fours, and gets one back checker over our blockade. However, fighting for the five point seems more important. Double-hitting is the best way to protect the blot on the five point, but that leaves their position a bit strung out. Their actual play looks best to me.
| Black to play 3-1. |
3. | 3-1: bar/24, 6/3* |
The loose hit on the three point is a must. It is vital to cut down on their ways to make their five point.
3. | . . . | 6-3: bar/22*/16 |
| Black to play 2-1. |
4. | 2-1: bar/23, 6/5 |
This sort of slot is usually correct when the opponent has slotted a key point he needs to make. The idea is that he probably won't be able to do everything at once. If he covers his blot, we will be happy to have slotted our five point. If he hits, this just gives us more ways to hit back. In this position there is no duplication and they have a few hit and cover numbers, but I believe it is worth taking the risk. The more conservative bar/22 or bar/23, 6/5 may be better, but I like our play.
4. | . . . | 4-4: 24/20*/16, 13/5 |
| Black to play 4-1. |
5. | 4-1: bar/21, 24/23 |
Shifting the anchor up to the two point is definitely correct. They have that pile of checkers on the eight point which are looking for a home. Making their two point limits the ways they can unload those checkers. This has priority over any other ace right now.
| Should White double? |
5. | . . . | 4-1: 8/4*, 6/5 |
| Black to play 5-2. |
6. | 5-2: bar/18 |
Coming out to their bar point is a must. We can't afford to have three checkers stuck on their two point now. As long as our position is fluid we will have plenty of winning chances.
| Should White double? |
6. | . . . | Double |
Now the double is good. They have a lot of rolls which make their four point, and some hit and cover numbers. If they roll one of these, they will definitely lose their market if they haven't done so already.
7. | Take |
We have the anchor on their two point. All our men are comfortably in play. Our offense is started. Most important, they haven't made their four point yet. True, most of their rolls make the point, but not all of them. I am confident that we have sufficient play to take this cube. Even though a Snowie rollout puts our cubeless equity at −.633 which would be a pass, I don't believe it. Our position just has too much potential.
7. | . . . | 5-5: 16/11(2), 8/3(2) |
| Black to play 5-3. |
8. | 5-3: 24/21*, 18/13 |
This is an interesting problem. The natural play appears to be 24/21*, 23/18. However, that abandons our back anchor for good, and we might need it in the future. White would have plenty of rolls which enter and hit in his inner board, and if we should flunk then White could carry out a blitz and our anchor on his bar point wouldn't do much good. Our actual play guards against this sort of accident. In addition, bringing another checker to the midpoint in order to help contain White's back checker can't be all bad. Of course making the defensive bar point is promising also. This puts pressure on White's outfield points, and this pressure could be important in the future. However, it is White who has the stronger inner board, and the blitz danger is there. I still like our choice.
8. | . . . | 6-1: bar/24, 11/5 |
9. | 4-4: 13/5(2) |
| White to play 6-1. |
9. | . . . | 6-1: 11/4* |
Even though they have only one man back, the loose hit is necessary. They have the stronger inner board, and if they can win the fight for their four point their position will improve greatly. 24/23, 11/5 is too ugly.
10. | 6-3: -- | 6-5: 13/7, 13/8 |
11. | 2-1: bar/24, 23/21* | 6-6: -- |
|
Should Black redouble to 4? |
12. | Double |
Something happened! Now we are very glad that our offense was already in place, since we don't have to spend time putting it together. Every checker we hit is automatically behind our four-prime. We have a triple shot at the blot on their bar point, and they have a checker on the bar. In addition, some of our misses (4−2 and 4−4) complete a five-prime. We have almost no bad rolls. If we make an improvement and they roll badly we could lose our market by a fair amount, and maybe we have already lost it. Redoubling has to be right.
12. | . . . | Take |
From their point of view, they are well ahead in the race and they have a good offense already in place. It is likely they will be hit and have two checkers on the bar, but we don't have the ammunition to carry out a blitz so they will probably will get an advanced anchor. We still have three checkers back, and there is no guarantee that we will be able to extricate these checkers before our opponents enter and are in position to carry out an attack. There has to be enough play in this position to justify a take. A Snowie rollout made their cubeless equity .479, which makes their take very clear. Our double is still fine, though.
| Black to play 1-1. |
13. | 1-1: 24/23, 13/12(2), 8/7 |
This is one of our few really poor rolls. Making the 23 point is mandatory. We must guard against a disaster. We felt that it was best to keep the outfield checkers together in case our opponents entered and hit on their four point and we flunked. This did not look like the time to leave any stray blots around. Tightening our belts appeared to have priority. However, we should have played 24/23, 8/5. This gives us more punch for making inner board points, and having the outfield checkers on the midpoint is just as good or better as having them on the 12 point. Why didn't we do this? The usual reason — we simply didn't see it.
| White to play 6-4. |
13. | . . . | 6-4: bar/15 |
This may be too optimistic. We are looking for a way to hit safely, and they are presenting this hit to us on a silver platter. They lose a lot of ground if we hit the checker on their bar point. I think they should hide the checker with bar/21, 7/1. How bad can this be? This play starts our four point, and we don't have the ammunition to attack there. Starting the ace point isn't bad — it is potentially the fourth point in their board. Hoping to make the bar point is hoping for a lot.
14. | 5-3: 23/18*, 21/18 |
| White to play 4-2. |
14. | . . . | 4-2: bar/21, 5/3 |
I would have been inclined to play bar/21, 24/22. They need to advance that checker on the 24 point, not hang back and get hemmed in. They are still ahead in the race, so hanging back doesn't make sense. We don't have the ammunition to attack. The spare on the three point may help attack our back checker, but it is unlikely that they will have the opportunity to do this. Whether they like it or not, the game is being played on our side of the board now.
| Black to play 5-3. |
15. | 5-3: 23/18, 7/4* |
This is a matter of assessing strengths and weaknesses. They have the stronger board, and we have the more compact blockade. If we play 18/10* that leaves four blots strewn around, and if we lose the blot-hitting contest it will be ugly. Our strength is in the outfield. Our play gets our back checker out of hock and plays with only one blot. We can live with that blot being hit. In addition, if they happen to miss then we are in position to extend our blockade and have a very strong advantage.
| White to play 2-1. |
15. | . . . | 2-1: bar/22 |
I agree. It is vital for them to go after an advanced anchor from where they can escape. If we win the fight for our four point, they will need to anchor on our three point or their position will collapse.
16. | 5-1: 8/3*, 4/3 | 6-3: -- |
| Black to play 5-2. |
17. | 5-2: 12/10*, 12/7 |
The choice of which five to play here is far from obvious. Each of the candidates has it merits. 12/10*, 10/5 brings a new builder in for the two and ace points, but fails to get the reinforcements closer. 12/10*, 12/7 gives us four builders for the four point while still holding the bar point, but otherwise doesn't diversify too well. 18/13, 12/10 covers the outfield better and prepares to make the eight point, but isn't as effective for the immediate attack. I was quite perplexed at the time as to which play was best, and I still have no idea.
17. | . . . | 4-2: bar/21, bar/23 |
| Black to play 5-3. |
18. | 5-3: 10/5, 8/5 |
Another difficult decision. My first inclination was to blast away with 7/4*, 6/1*. This fights for our four point and has a big upside if it works. An even bigger play is 7/4*, 7/2*, which goes after a better point and leaves better builder distribution but loses the bar point and is very accident prone. the double-hitting plays have high gammon potential for both sides. A quieter attacking play is 18/13, 7/4*, which keeps some structure but leaves more ways for them to hit back on our four point. 8/3, 7/4* is an even more conservative way to hit loose, but the third checker on the three point may not work out well. And then there is the quiet 10/5, 8/5.
I didn't care for this, but my partner was quite strong on it. He argued that we were already ahead in the race, we had escaped all of our back checkers, and their inner board was as strong as ours. It wasn't the end of the world if they got our four point, and our distribution would still be good for attacking purposes next roll. These were sound arguments and I wasn't comfortable about the position, so I agreed to his choice. Short rollouts appear to indicate that he was correct.
This is the way a doubles team should function. When one partner isn't sure about the play and the other partner is confident, then the player who is confident is likely to be correct. As long as egos don't get in the way and the players are honest about which plays they are confident of and which ones they aren't sure of, this approach will work very well.
| White to play 6-3. |
18. | . . . | 6-3: 24/21, 23/17 |
Grr — why didn't we double-hit?
| Black to play 5-2. |
19. | 5-2: 18/16, 7/2 |
It seemed natural to split one checker from their bar point in order to give us better outfield coverage. Perhaps this is not correct, since we have both the racing lead and the more advanced anchor. It could be costly if we are hit. The outfield coverage may not be so important, since they aren't going to be in a rush to release their back anchor anyway. More likely they will be using their next roll or two to build up their inner board, and the checker on the 16 point will be sort of hanging in limbo.
| White to play 6-3. |
19. | . . . | 6-3: 8/2, 5/2 |
This looks better than running with 17/8 and conceding the outfield to us. That four-point board is very menacing.
| Black to play 6-4. |
20. | 6-4: 16/6 |
Hitting with 18/8* is suicidal. We would have far too many blots. This is an illustration of why our previous play may not have been correct.
| White to play 6-6. |
20. | . . . | 6-6: 21/9(2) |
Their play leaves the indirect shot, but it paves the way for a safe trip home in the future. 21/15(2), 17/5 is safe, but clearing the 15 point will be a problem in the future. They now have a small lead in the race and we have an inner board blot, so their approach seems reasonable.
| Black to play 6-4. |
21. | 6-4: 18/8* |
This time we have to hit. If we don't, we are just taking the worst of it. At least we have fewer blots and there is a greater element of duplication than last roll.
21. | . . . | 6-4: bar/15 |
| Black to play 5-1. |
22. | 5-1: 18/12 |
This is just a matter of fewest shot numbers. Everything else is secondary.
|
Should White redouble to 8? |
1) The race is dead even (they are behind 4 pips but on roll). Thus if they double and miss the shot, they turn themselves into underdogs instead of favorites because we would then own the cube.
2) Their board isn't solid. This means that a hit won't necessarily win for them if they double now. It also means that the market loss involved when they hit isn't as great as it would be if they had a solid board.
3) They are one point ahead in the match, and the cube is getting up there. Because of this, we would have more leverage holding an 8-cube than we would if the match score were even.
22. | . . . | 6-1: 15/9, 8/7 |
23. | 5-3: 7/4, 7/2 | 5-3: 9/4, 7/4 |
| Black to play 5-2. |
24. | 5-2: 12/7, 8/6 |
This play is probably wrong. Our fours could become awkward very quickly if we don't get another checker onto the four point now. I think we should have played 12/7, 6/4 and gone for the better future distribution rather than the immediate crossover.
24. | . . . | 5-4: 9/5, 9/4 |
25. | 5-3: 7/4, 5/off | 6-2: 8/off |
26. | 2-1: 6/5, 2/off | 6-4: 6/off, 4/off |
27. | 3-2: 3/off, 2/off |
|
Should White redouble to 8? |
27. | . . . | Double |
Certainly a correct redouble with a 7-pip lead and a relatively smooth position.
28. | Take |
If it were just a question of the pipcount, this would be a borderline pass — we are a little worse than 2 pips away from the 10% mark (behind 7 pips when the leader has 48 pips to go). However, all the other factors argue in favor of the take:
1) We have one more checker off than they do. Checkers off mean a lot in races. Our structure is perfect, while they figure to waste a bit.
2) We are behind in the match. This means that if and when we send it back to 16 our odds on the redouble are a little better than if the match score were even, and their odds on the take are a little worse. Thus, we have more recube leverage than we would have at an even match score.
These factors make it a clear take. Snowie data base confirms this, giving us 24% winning chances cubeless. Add in our recube vig, and it isn't close. It is difficult to take this sort of cube when you know the match is likely to be riding on the result, but you gotta do what is right.
28. | . . . | 5-3: 5/off, 3/off |
29. | 4-1: 5/off | 5-2: 5/off, 2/off |
30. | 3-2: 5/off | 4-2: 4/off, 2/off |
| Black to play 3-2. |
31. | 3-2: 4/2, 3/off |
6/4, 3/off might be better. I follow the principle that I'm going to need a bunch of sixes to have much of a chance, so I assume that I will roll those sixes and I want to leave the best structure on that assumption. If the race were closer, I would have played 6/4, 3/off.
31. | . . . | 6-5: 6/off, 5/off |
32. | 4-3: 6/3, 4/off | 5-3: 6/1, 3/off |
33. | 6-6: 6/off(3), 5/off | 1-1: 3/off, 1/off |
34. | 2-1: 3/off | 6-2: 4/off |
Single game |