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Subject: Re: Drawn endgame?

Author: Russell Reagan

Date: 18:35:42 05/30/02

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On May 30, 2002 at 19:31:23, pavel wrote:

>I, with my patzer knowledge think that black can still quize a win here.
>But am I wrong? Is there something obvious that I am missing?

>[D]8/8/5P2/1K6/8/1P1k2Bp/7P/5r2 b - - 0 1

I'll give you my patzer thoughts. The pawn on f6 is lost. Now the question is:
Can black win using only his rook? If black can win using his rook, then he
*might* be able to win. If he can't win using his rook (if the bishop could
fight it off enough), then the only way to win is if he can promote his pawn.
The only way he can promote his pawn is to capture the white bishop with his
rook, have the pawn recapture, then push his h-pawn.

I think that because of the white bishop, black cannot win with only his rook
and king. So he must promote. To promote, he would have to get white's h-pawn
off h2. To do that he has to capture either white's bishop or h-pawn,
sacrificing his rook. If black attacks white's bishop with his rook, white will
simply move the bishop out of harm's way, so black cannot promote his pawn by
capturing the bishop first. So black will have to move his king to attack h2,
then capture the pawn on h2 with his rook, then capture the bishop with his king
after the bishop recaptures the rook.

It will take black's king 3 moves to get into position, and it will take the
rook 3 moves to get into position (remember, it must capture on f6 first).
That's 6 moves minimum, and that's just to get in place. Black still needs 5
more moves to promote his pawn. That's 11 moves total to promote the black pawn.
To promote the pawn, you must have the rook AND king involved in breaking down
white's defense in that corner. Without either one of those, you can't promote
the pawn.

So, your options are (as black):

1. Go for the promotion
2. Check the white king over and over

If you go for the promotion, white will promote long before black will. So
option 1 is no good. If you check the white king over and over trying to force a
draw, the bishop will be able to block the rook eventually, and white can still
make progress.

I think white wins, or draws at worst. I don't think black can win.

Russell



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