Author: Uri Blass
Date: 12:25:24 08/14/00
Go up one level in this thread
On August 14, 2000 at 14:59:07, Christophe Theron wrote:
>On August 14, 2000 at 05:34:09, Alvaro Rodriguez wrote:
>
>>On August 14, 2000 at 02:50:51, Christophe Theron wrote:
>>
>>>On August 14, 2000 at 00:25:54, Ed Schröder wrote:
>>>
>>>>On August 13, 2000 at 23:04:06, robert blackwell wrote:
>>>>
>>>>>People should check out a position more carefully before claiming a move is bad.
>>>>>bxa2 in the position given in the earlier post is the right move and it is the
>>>>>move nd5 which loses as it breaks the pin on the d file preventing bxb3! any
>>>>
>>>>1..Bxa2 2.b3 Nd5 and black holds the position. If this is what you
>>>>mean I am in agreement.
>>>>
>>>>Ed
>>>
>>>
>>>That's what Tiger thinks, indeed. But I still believe that Tiger should not take
>>>the pawn in a2. It is probably losing in the long term (but giving white a hard
>>>time and many ways to lose).
>>>
>>>Playing b3 quickly does not work. After a 20 plies search the bishop was still
>>>there and black's position was not so bad. Actually it's white that has to play
>>>very carefully in order to hold the position.
>>>
>>>
>>> Christophe
>>
>>I agree, the position is very complicated, and I think we might need some more
>>example of this kind of positions.. Bxa2 looks very bad, but maybe it isn´t..
>>Maybe Bob have something to show us from the ICC games..
>>
>>Regards,
>>Alvaro
>
>
>
>Here is another unclear position that Uri has sent to me some time ago.
>
>[D]r2nkb1r/pp1n2pp/8/1P1pp3/8/2P1B3/1P3PPP/RN2KB1R w KQkq - 0 1
>
>I think that Rxa7 Rxa7 Bxa7 is bad because black plays b6 and the bishop is
>trapped.
>
>What does your favorite chess program think of this one?
>
>
>If somebody has "obvious" positions where the bishop is "obviously" trapped and
>will be "obviously" lost, I'm very interested.
>
>The position must meet two conditions:
>
>1) the program must not be able to see that the bishop is losing by search (the
>loss must be 7 to 8 full moves away).
>
>2) it must be obvious that the bishop is hopelessly lost.
>
>
>
> Christophe
Junior5.4 saved this engine-engine game but I suspect that the reason is lack of
tablebases for crafty16.6.
I am not 100% sure that Rxa7 is losing the bishop and the game but I am sure
that white has to fight for a draw after Bxa7.
It is not obvious that the bishop can be captured in the future(maybe white can
defend it all the game but even in this case white cannot get the initiative
because it has to defend the bishop).
Here is all the game:
[Event "120/40+60/20+30/game"]
[Site "?"]
[Date "1999.04.04"]
[Round "1"]
[White "Junior 5.4"]
[Black "Crafty 16.6"]
[Result "1/2-1/2"]
[ECO "D02"]
[Annotator "Uri"]
[PlyCount "204"]
[EventDate "1999.04.02"]
{131071kB, Jun-book.ctg. K6-2-350} 1. d4 {0} 1... d5 {2} 2. Nf3 {0} 2... Nf6 {2
} 3. Bf4 {0} 3... c5 {2} 4. e3 {0} 4... Nc6 {2} 5. c3 {0} 5... Qb6 6. Qb3 {
0.15/15 254} 6... Qxb3 {0.28/11 213} 7. axb3 {0.23/15 103} 7... cxd4 {
0.27/11 260} 8. exd4 {0.27/15 165} 8... e6 {(Bf5) 0.27/12 204} 9. b4 {
(Be2) 0.34/17 208} 9... Bd7 {(Be7) 0.38/12 376} 10. Ne5 {(Be2) 0.39/17 352}
10... Nh5 {0.45/12 222} 11. Be3 {0.45/16 203} 11... Nf6 {0.51/12 200} 12. Nxd7
{0.40/16 219} 12... Nxd7 {0.46/13 198} 13. Bf4 {(Be2) 0.39/17 152} 13... f6 {
0.54/12 198} 14. b5 {(Be2) 0.33/16 243} 14... Nd8 {(Ne7) 0.59/12 198} 15. Be3 {
(Bc7) 0.35/16 175} 15... e5 {(Bd6) 0.40/12 198} 16. dxe5 {(Be2) 0.46/17 379}
16... fxe5 {0.35/12 202} 17. Rxa7 {(b6) 0.58/17 155} 17... Rxa7 {0.16/13 197}
18. Bxa7 {0.57/16 62} 18... b6 {0.15/12 197} 19. g3 {0.54/17 211} 19... Ne6 {
0.21/13 198} 20. Bg2 {0.62/15 136} 20... e4 {0.44/12 213} 21. Nd2 {
(f3) 0.53/16 308} 21... Bc5 {(Bd6) -0.17/11 201} 22. Nb3 {(Ke2) 0.52/16 268}
22... Ke7 {(Rf8) -0.16/11 206} 23. Ke2 {0.49/16 245} 23... Rf8 {-0.22/12 196}
24. Rf1 {0.55/15 143} 24... Ra8 {(Kd6) -0.03/11 203} 25. Ra1 {0.39/16 238}
25... Rf8 {0.00/11 197} 26. Nxc5 {(Rf1) 0.39/14 138} 26... Nexc5 {-0.06/13 195}
27. f3 {(b4) 0.40/15 172} 27... Rf5 {(Kd6) -0.24/11 214} 28. fxe4 {0.67/15 211}
28... Nxe4 {-0.11/12 194} 29. Bxe4 {(Bh3) 0.72/16 342} 29... Re5 {
(dxe4) -0.13/13 198} 30. Ra6 {(Ra4) 0.76/16 286} 30... Rxe4+ {
(Re6) -0.47/14 198} 31. Kd2 {(Kd3) 0.78/16 292} 31... Re6 {-0.30/14 197} 32. b4
{(Kd3) 0.69/17 124} 32... Kd8 {(Kf6) -0.80/13 192} 33. Kd3 {0.39/18 144} 33...
Kc7 {-0.79/15 194} 34. g4 {(h3) 0.00/15 119} 34... g5 {(Ne5+) -0.99/14 192} 35.
h3 {(Kd4) -0.43/17 108} 35... Rh6 {-1.48/15 192} 36. Kd4 {-0.92/19 451} 36...
Rxh3 {-1.84/15 192} 37. Ra4 {(Bxb6+) -0.84/17 240} 37... Rg3 {-2.14/14 192} 38.
Ra6 {-1.11/16 103} 38... h6 {-2.18/14 192} 39. Kxd5 {-1.31/16 110} 39... Rxc3 {
-2.67/14 191} 40. Ra1 {(Ra2) -1.57/16 104} 40... Rd3+ {(Rg3) -2.81/14 96} 41.
Ke4 {-1.66/17 140} 41... Rd2 {(Rb3) -2.89/14 185} 42. Kf5 {(Rc1+) -1.73/16 272}
42... Rd5+ {-3.04/14 185} 43. Kg6 {-1.90/17 201} 43... Ne5+ {-3.46/15 185} 44.
Kxh6 {-2.03/16 153} 44... Nxg4+ {-3.54/15 185} 45. Kh5 {-2.10/16 159} 45...
Nf6+ {-3.58/14 187} 46. Kg6 {(Kh6) -2.12/17 160} 46... Nd7 {-3.31/14 377} 47.
Rg1 {(Kf7) -2.53/17 673} 47... g4 {-3.87/14 222} 48. Kf7 {-2.58/16 127} 48...
Rd4 {(Rxb5) -4.45/14 171} 49. Kg6 {(Ke6) -2.20/16 279} 49... Rxb4 {
(Ne5+) -4.50/14 168} 50. Kf5 {-1.59/15 122} 50... Rxb5+ {(Kb7) -4.55/14 166}
51. Kxg4 {-0.54/14 121} 51... Ra5 {(Rb4+) -4.55/14 167} 52. Bxb6+ {
(Rc1+) -0.54/17 129} 52... Nxb6 {-4.60/14 166} 53. Kf4 {(Kf3) -0.55/17 104}
53... Nd5+ {(Kd6) -4.60/12 166} 54. Ke5 {(Kf5) -0.58/17 111} 54... Nc3+ {
-4.60/12 220} 55. Ke6 {-0.64/18 117} 55... Ne2 {-4.60/12 169} 56. Rg4 {
(Rd1) -0.69/18 182} 56... Rc5 {-4.60/13 205} 57. Re4 {-0.71/18 146} 57... Nc3 {
(Rc6+) -4.60/14 143} 58. Rd4 {(Rg4) -0.71/19 185} 58... Kc6 {
(Rc6+) -4.60/13 155} 59. Rd6+ {(Kf6) -0.72/19 130} 59... Kb7 {
(Kb5) -4.60/14 137} 60. Rd7+ {(Rd4) -0.70/18 97} 60... Kc8 {(Kb6) -4.60/13 69}
61. Ra7 {(Rd3) -0.62/17 51} 61... Rh5 {(Rc4) -4.60/12 54} 62. Ra1 {
(Rg7) -0.61/16 40} 62... Kd8 {(Rh6+) -4.60/11 52} 63. Ra7 {(Rg1) -0.68/16 51}
63... Nb5 {(Rh6+) -4.65/12 51} 64. Rd7+ {(Ra8+) -0.60/16 49} 64... Kc8 {
-4.60/14 49} 65. Rf7 {(Rd2) -0.56/15 56} 65... Nc7+ {(Rh6+) -4.60/11 50} 66.
Kd6 {-0.49/16 48} 66... Kb8 {(Rh6+) -4.60/12 46} 67. Rd7 {(Kc6) -0.44/16 40}
67... Rg5 {(Rh6+) -4.55/12 45} 68. Kc6 {-0.41/17 36} 68... Rg6+ {
(Rg8) -4.45/12 54} 69. Rd6 {-0.30/17 31} 69... Rg8 {-4.50/13 42} 70. Rd1 {
(Rd7) -0.33/16 42} 70... Kc8 {(Ne6) -4.50/11 42} 71. Rc1 {(Rf1) -0.36/16 70}
71... Rg5 {(Rg6+) -4.55/11 75} 72. Kb6 {(Rf1) -0.32/16 31} 72... Rb5+ {
(Rg6+) -4.55/12 38} 73. Kc6 {-0.45/16 12} 73... Ra5 {(Rh5) -4.55/12 38} 74. Rh1
{(Kb6) -0.31/15 34} 74... Ne6 {(Ra6+) -4.60/11 43} 75. Kd6 {-0.30/16 89} 75...
Nf4 {(Nd8) -4.55/11 34} 76. Rc1+ {-0.33/14 33} 76... Kd8 {-4.55/12 33} 77. Rd1
{(Rc5) -0.28/16 39} 77... Ng6 {(Nh5) -4.55/11 32} 78. Rc1 {(Rd5) -0.47/14 24}
78... Nh4 {-4.55/11 34} 79. Rd1 {(Rc5) -0.35/15 34} 79... Ra6+ {-4.55/11 31}
80. Ke5+ {-0.52/14 45} 80... Ke7 {-4.55/12 31} 81. Rd3 {(Ke4) -0.48/14 22}
81... Re6+ {(Ng6+) -4.60/11 29} 82. Kf4 {(Kd5) -0.55/16 88} 82... Ng6+ {
(Kf6) -4.60/11 28} 83. Kg5 {(Kg3) -0.41/17 24} 83... Kf7 {(Nh8) -4.60/11 27}
84. Rd5 {(Rd7+) -0.39/16 27} 84... Re4 {(Ne7) -4.65/11 27} 85. Rf5+ {
-0.35/16 22} 85... Kg7 {-4.65/13 26} 86. Rd5 {(Rf2) -0.36/17 34} 86... Ne7 {
-4.65/12 25} 87. Rd6 {-0.26/15 22} 87... Rc4 {(Re5+) -4.60/11 27} 88. Rd2 {
(Re6) -0.28/14 23} 88... Rb4 {(Rc7) -4.65/11 23} 89. Rd3 {(Rg2) -0.30/16 46}
89... Kf7 {(Rb5+) -4.65/11 27} 90. Rd6 {(Rf3+) -0.33/14 15} 90... Nc8 {
(Rb5+) -4.60/11 23} 91. Rf6+ {(Rh6) -0.37/14 18} 91... Ke7 {-4.60/12 21} 92.
Rf4 {-0.44/15 20} 92... Rb1 {-4.65/12 21} 93. Re4+ {(Rf2) -0.45/15 28} 93...
Kd6 {(Kf7) -4.65/12 20} 94. Kf4 {(Kg4) -0.44/14 15} 94... Nb6 {
(Ne7) -4.65/11 21} 95. Ke3 {(Kg5) -0.46/14 18} 95... Nd5+ {(Ra1) -4.65/10 19}
96. Kd3 {-0.36/13 19} 96... Rb3+ {(Ra1) -4.60/10 20} 97. Kc4 {(Kd4) -0.17/14 16
} 97... Ra3 {(Rb4+) -4.55/11 24} 98. Re8 {(Kd4) 0.00/15 19} 98... Nf4 {
(Ra4+) 0.00/10 21} 99. Rd8+ {(Rc8) 0.00/18 12} 99... Ke7 {(Ke5) 0.00/14 18}
100. Rh8 {0.00/20 23} 100... Kd6 {(Ra4+) 0.00/14 16} 101. Rd8+ {0.00/29 12}
101... Ke5 {0.00/60 1} 102. Rd1 {(Re8+) 0.00/61 3} 102... Ne2 {0.00/60 0}
1/2-1/2
Uri
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