In the first round of BBD1 two players of the Brussels Four Cubes team were pitted against each other. Zsolt Tasnadi and Alain Chif have worked their way up the national ranking to the edge of the top-10. They are working hard to make the step from Intermediate to Advanced level.
Their match was witnessed by nobody except the camera. All other players were completely wrapped up in their own decision-making processes. Their matches have disappeared into nothingness. The Tasnadi-Chif match, however, has now been transcribed in XG and fully annotated. If you are a member of BGFed, you can send me an e-mail (firstname.lastname@example.org) and we (i.e. Zsolt, Alain, and I) will share this fascinating contest with you. You can review it at leasure and – hopefully – learn something from the annotations.
Game 3 was particularly instructive. Zsolt is leading 2-1, which makes this a 5-away 6-away game. This is a very challenging match score, especially when the cube has been turned. It requires some in-depth understanding to fully grasp the implications of re-cube action. Fortunately for us, this is no issue here, as the game played itself out with the cube in the middle. Let us see what happened :
Zsolt Tasnadi (Red) needs 5 Alain Chif (White) needs 6
1. —– 61 : 13/7 8/7
2. 61 : 13/7 8/7 41 : 24/20 24/23
3. 43 : 24/20 24/23 52 : 13/8 6/4*
4. 61 : bar/24 20/14 52 : 13/8 6/4
5. 31 : 8/5* 6/5 62 : bar/17*
6. 31 : bar/22 6/5 ?
This is a borderline No Double for money, but ats ( = at the score), White can turn the cube. White’s Gammon Value (GV) is slightly higher and so is Red’s Takepoint (TP). White is up 21 pips in the race, has a better position (one checker semi-escaped + the bar- and 4-point) and some powerful threats.
White’s Winning Chances: 66,23% (G:20,00% B:0,72%)
Red’s Winning Chances: 33,77% (G:7,11% B:0,26%)
No double: +0,763 (-0,076)
Double/Pass: +1,000 (+0,160)
Best Cube action: Double / Take
6. 65 : 23/17 8/3*
7. 31 : bar/22* 6/5 61 : ?
61 : bar/24 17/11
After entering with the ace, White cannot afford to give up the 17-point. Alain must be suffering from early morning drowsiness, because this is an error you cannot afford to make. With a stranded checker on the 24-point, you simply must keep the 17-point to keep that man connected. This is a bad mistake (0,166) simply because the correct move is so obvious.
8. 21 : 6/4 5/4 61 : ?
Alain is lucky to have rolled a joker, but unlucky in that there is such an attractive alternative (with a 63 the choice would be crystal clear). How can making the 5-point be wrong? Well, this is a pvp-position (prime-vs-prime) and this territory is governed by different laws. A useful guideline is : Do what is most difficult first. Here, your back man is away from the edge of a 4-prime, so he can only successfully jump to the 17-point with 61 and 52 (4 rolls out of 36). Making the 5-point is much more probable : 61, 63, 31, 66, 44, 33, 11 do the job (10/36).
Still, the resulting position after Alain’s move is worth a look :
It is easy to see the lure of this position : White has a 5-prime with a spare and only one man behind a stripped 4-prime. Red on the other hand has 2 men behind a 5-prime. The value of the assets is clearly in White’s favour. However, the problem is that Red is on roll : 15 rolls hit the blot on the 17-point and nine 2s anchor up (Red hits with 32). In other words, Red’s initiative negates his positional disadvantages. This is a very important concept in pvp-games. By the way, I would not be surprised if chess players were more likely to go for the 5-prime here than non-chess players.
Another aspect is the cube. After reconnecting with the blot on the 17-point, White is close to a Double if Red does not roll something spectacular like 42, 62, 64 or 22. After making the 5-point, Red has 5s that hit and 2s that anchor, leaving a No Double, Take position. The computer labels this a monstrous blunder (0,447). However, pvp-positions are notoriously complex, so I would not beat myself up over this, had I got it wrong.
1. XG Roller++ 24/17 eq:+0,759
Player: 66,98% (G:13,44% B:0,42%)
Opponent: 33,02% (G:5,81% B:0,19%)
2. XG Roller++ 24/23 17/11 eq:+0,388 (-0,370)
Player: 58,16% (G:14,58% B:0,63%)
Opponent: 41,84% (G:10,23% B:0,35%)
3. XG Roller++ 11/5 6/5 eq:+0,312 (-0,447)
Player: 55,27% (G:16,33% B:0,79%)
Opponent: 44,73% (G:11,74% B:0,53%)
9. 31 : 13/9 22 : ?
Alain was not punished for his mistake and should have doubled here. Failing to do so, costs 0,112. Once again, the dice offer him a tricky choice : one might be tempted to make a full 6-prime with 13/9 (2). Alain keeps a cool head though and finds the right priorities : safety the blot (17/13), come to the edge of the prime (24/22) and put a spare on the 6-point (8/6). Well played!
10. 31 : 13/9 44 : ?
It is almost comical how Alain is once again confronted with a great roll which is so difficult to play. What would you do? Surely one looks at 13/9 (2) 13/5, right? This builds a 6-prime with a great distribution of spares. However, this is a massive blunder, costing 0,342! The key to this position is that Alain is behind a broken 5-prime himself and needs to roll a 5 to escape. Chances of doing that are only 30% (11/36), so that may take a few rolls. Alain’s timing is precarious : his 6-prime may only hold for one or two rolls if a 5 does not come quickly. Therefore he needs to prevent Red from either counter-priming or attacking him. This is achieved by putting Red on the bar. Several plays are worth considering, but the best way to do that is to point-and-shift : 7/3* (2) 5/1* (2)(!!). Congrats to the reader if he got this one right.
1. XG Roller++ 7/3*(2) 5/1*(2) eq:+0,958
Player: 67,28% (G:47,04% B:0,45%)
Opponent: 32,72% (G:6,25% B:0,35%)
11. 32 : 24/22 13/10 53 : 22/14 (the required 5)
12. 51 : 9/3 32 : 14/11 6/4
13. 41 : 9/8 7/3 Double to 2
After this game the score was tied at 2-2 (7). Game 4 turned into an exciting blitz : Alain found a world-class Take and Zsolt struggled with the checker-plays. You can review this game and the rest of the annotated match by simply sending me an e-mail (see above).