Author: Brian Katz
Date: 03:24:21 01/15/04
Go up one level in this thread
On January 15, 2004 at 01:45:45, Ricardo Gibert wrote:
>On January 15, 2004 at 00:19:10, Chesster Fritz wrote:
>
>>On January 14, 2004 at 22:57:32, Sally Weltrop wrote:
>>
>>>[d]8/1B6/3k3p/pK4p1/P1P3P1/7P/5b2/8 b - - 0 49
>>>
>>>Svidler resigns!!!
>>>
>>>Looks like a draw to me and other engines that I have used.
>>
>>Yes it appears to be drawn, but I'm not so sure about that.
>>Computers will be of little help solving this ending imo.
>>
>>White, even though there are Bishops of opposite colour, has an advanced passed
>>pawn, and though it can't Queen, may be Black's undoing, caution at every turn
>>must be used not to lose on the King-Side. With a very deep analysis, it may be
>>a complex win for White. I wouldn't resign so quickly, but I'd be very troubled
>>by this position if I were Black.
>>
>>Maybe this will turn up as a brilliant endgame study in the future.
>>I'm interested on what both Kramnik and Svidler have to say about this game.
>
>White's advantage is purely optical in nature. It's a stone cold draw.
>
>>
>>It's late here, but I may take a stab at it myself, albiet I doubt I'll come up
>>with a definitive answer.
>>
>>This ending takes the highest level of technique, and I'm not Capablanca or
>>Svidler!;-)
>>
>>Most likely we'll see some good analysis from these Grandmasters, (Not
>>Capablanca) unhappily deceased;-), but from Kramnik, Svidler, and other GMs.
>>
>>Fritz
Fritz 8, Hiarcs 8 AMD Athlon XP 2600+ choose:
1.Kc7...which appears to lose in the end, (although both playout the position
differently)
Whereas Crafty 19.08 chooses 1.Bd4...allowing the capture of the a5 pawn with
2.Kxa5 Kc5 3.Bd5 Be5 4.Ka6...and then 4...Bc3 5.a5 Bb4 and the White King cannot
make it to the Queenside without giving back the a-pawn which would then be
drawn.
This ending sure does APPEAR to be drawn if Black immediately plays 1...Kc7!
driving the White Bishop away and forever controling c7 and then follows with
2...Be1 defending it's a5 pawn.......
......BUT THIS SEEMS TO BE ONLY AN ILLUSION! AND SEEMS LOST FOR BLACK......
Perhaps some of you can show a forced win or draw.
......As White can eventually get it's c-pawn to c6 defended by it's Bishop and
White's King can get to g6 and win the h-6 pawn, but then Black's Bishop goes to
a4 to defend it. Then White shifts his King back to the Queenside to attack the
a5 pawn. Black then has to defend it by placing his Bishop on the e1-a5
diagonal.
Even if Black times it just right whereas his Bishop gets to e1 to defend the a5
pawn, when White's King gets to b5 while the c6 pawn is defended by the White
Bishop, White then throws in the pawn sacrifice
1.h4! gh 2.g5...
and then the pawn advances to g6. Black's Bishop then has to keep and eye on g7
while White's King is on b5 attacking the a-pawn and his White Bishop is
defending his c6 pawn. Black's King stays on c7. At that point, White makes a
waiting Bishop move while it still defends the c6 pawn and still controlling h1
to prevent Black from Queening. Black must move it's Bishop from c3( assuming it
was on the ideal square c3 simultaneously defending g7 and the a5 pawn) while
still defending g7 thus allowing the capture of the a5 pawn and WINNING FOR
WHITE!
IF rather than moving the Black Bishop from the ideal c3 square, Black moves his
King to b8 c8 or d8, White's King advances to b6 threatening to advance the pawn
to c7 with check and then it's Bishop to the h3 c8 diagonal checking the King
and the Queening with Check or if the Black King were on c8, it gets hit with
the Bisop Check followed by c7 check and White Queens. If the Black Bishop goes
to e5 to prevent the pawn advance to c7, Black then loses the a5 pawn and loses
the game.
HOWEVER
Some other engines choose to play 1...Be1 first, allowing 2.Kc6 and then the a5
pawn is eventually lost. But with a Black Bishop on a5 (after taking the a5
pawn) and Black King on d6, White's King is stuck on the Queenside of the Board.
If somehow White sacs the c-pawn allowing ...Kxc5 the White King can then make
it over to the Kingside and win the h6 pawn but then we get into a position
where Black defends the g-pawn with ...Bh4 and the Bishop stays there as long as
the King is attacking the g-pawn. Meanwhile the Black King stays on a5 or a7
forever, and no progress is made. Or we can have a position where White
eventually gives up the a-pawn after Black's a-pawn has been captured, and again
we have a drawn position where the Black King controls c5 or c7 forever stopping
White's c-pawn and the Black Bishop again stays on h4 to defend the g-pawn after
White plays Kxh6...
This is a fascinating position.
1...Kc7 appears to hold the draw, but seems to lose!
and
1...Be1 appears to lose the game, but seems to draw! Perhaps this is why Svidler
resigned. He may have just tossed this variation aside, because he would then be
down 2 pawns. But White has to give one of the Queenside pawns back to get his
King to the Queenside, and this draws.
At first glance it appears the Black may have a draw with 1...Kc7, but it seems
that White just alternates back and forth combining threats and eventually Black
has to give somewhere. On the other hand, 1...Be1 appears to lose because the a5
pawn is lost but then Black's King and Bishop combine forces to control the
Black King's access squares to the Kingside, and White then has to sac a KEY
c-pawn to divert the Black King, but this pawn is needed to win the game.
Grandmasters at that level see into positions like this much faster than you and
I, although they do falter and botch won games and throw away drawn games. In
this case, it appears that Svidler may have been incorrect in his decision.
Please give your views on this position and correct my views if necessary as
well.
Look forward to hearing from you.
Brian
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