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Subject: Re: Testposition - Bishop ending

Author: Sune Larsson

Date: 19:29:16 04/24/02

Go up one level in this thread


On April 24, 2002 at 18:38:16, Oliver Roese wrote:

>On April 24, 2002 at 17:00:09, Sune Larsson wrote:
>
>>On April 24, 2002 at 15:46:11, Oliver Roese wrote:
>>
>>>Hi!
>>>
>>>On April 24, 2002 at 13:34:21, Sune Larsson wrote:
>>>
>>>>
>>>> [D]8/2b1Bp1k/2p3pP/4P1P1/2P1K3/8/8/8 w - - 0 52
>>>>
>>>> Every program I've tried so far seems to think that this position
>>>> is won for white. There are evals of more than +3.00. White is a pawn
>>>> up but it's a dead draw.
>>>>
>>>> White's king has three doorways to heaven, a5, c5 and e5.
>>>> But black's bishop is closing everyone of them:
>>>>
>>>> 1) The white king moves to a4 and tries to enter via a5.
>>>>    Black keeps the bishop on c7 and shuffles the king.
>>>>
>>>> 2) The white king moves to b4 or d4 and tries to enter via c5.
>>>>    Black puts the bishop on b6.
>>>>
>>>I am sorry to oppose but here is the weak point. Lets assume this position would
>>>arise:
>>>[D]6k1/5p2/1bp2BpP/4P1P1/1KP5/8/8/8 w - - 0 1
>>>White breaks through and gives his pawn e5 for pawn c6. Two passers
>>>are enough to win, e.g::
>>>1.Be7 Kh7 2.Bc5 Bd8 3.Be3 Bc7 4.Kc5 Bxe5 5.Kxc6 and white wins easily.
>>>
>>>Oliver Roese
>>
>>
>>
>> [D]6k1/5p2/1bp2BpP/4P1P1/2P5/1K6/8/8 b - - 0 1
>>
>>
>> Before the white king reaches b4, black must play 1.-Ba5! keeping
>> the resource 2.-Bd2! =
>>
>> Sune
>
>You are right, that's it.
>I couldn't find another idea to win, so it seems this position is a draw.
>Pretty amazing, i think.
>Where does this position come from?
>Oliver


 The original test position was from a game of mine vs Fritz 7 (game 120 min),
 which was previously posted here. Fritz (white) misplayed the ending to
 reach the position on top of this post. The game was drawn.

 Sune




>
>
>>>
>>>
>>>> 3) All the time black prevents the possibility 1.e6 fxe6 2.Ke5
>>>>    by keeping the bishop on c7.
>>>>
>>>> 4) If white plays his bishop to f4, threatening 1.e6 black plays
>>>>    1.-Bb6. Then 2.e6 fxe6 3.Ke5 is met by Bc7+
>>>>
>>>> 5) And black has a million of Kg8-h7 moves while white cannot make
>>>>    any progress at all. 1.Bd6 Bd8 is nothing. All c5 moves from white
>>>>    are just voluntarily closing one possible path for the king.
>>>>



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