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Date: 22 Jun 2006 00:24:49
From: Antonio Torrecillas
Subject: pawn ending
Some days ago I proposed this game to study:

[Event "Match des Legendes"]
[Site "Porto Vecchio FRA"]
[White "Spassky, B."]
[Black "Karpov, Ana"]
[Result "1-0"]

1. e4 c6 2. d4 d5 3. Nc3 dxe4 4. Nxe4 Nd7 5. Nf3 Ngf6 6. Nxf6+ Nxf6 7.h3
Bf5 8. Bd3 Bxd3 9. Qxd3 e6 10. O-O Be7 11. c4 O-O 12. b3 c5 13. Bb2 cxd4
14. Rfd1 Qa5 15. Bxd4 Rfd8 16. Qe2 Qf5 17. Rd3 Qe4 18. Qxe4 Nxe4 19.Rad1
Kf8 20. Kf1 f6 21. Be3 Rxd3 22. Rxd3 Ke8 23. Nd2 Nxd2+ 24. Rxd2 a6
25.Ke2 Rd8 26. Rxd8+ Kxd8 27. c5 Kd7 28. Kd3 Bd8 29. b4 Bc7 30. Kc4 h5
31. a4 Be5 32. b5 axb5+ 33. axb5 Kc7 34. g4 hxg4 35. hxg4 Kd7 36. f4 Bb2
37. f5 e5 38. Kd5 Ba3 39. g5 fxg5 40.Bxg5 Bb2 41. Bh4 Bc3 42. Bg3 1-0

I wrote about the engine suggestion 28....Kc6!! and I showed some
tactical details about it in previous messages.

The second all engine suggestion was 35...g5. I think that proposition
to be a mistake. Maybe engines can not see too far in that ending.
I would like to add some analysis about it. Let's see!

FEN:
8/1pk5/4pp2/1PP1b1p1/2K3P1/4B3/5P2/8 w - g6 0 36

ASCII
wKc4,Be3,Pb5,c5,f2,g4
bKc7,Be5,Pb7,e6,f6,g5

White can obtain a pawn ending with 36.Bd4 Bxd4 37.Kxd4 Kd7
In that ending white has a passed pawn in the queen wing which can be
used as distraction to win the game in the kings wing. The problem is
that white king has no accesss to king wing.

White has two possible ideas:
- To open king wing with f4. The problem is that there are too many
simplifications. I think that possibility do not work.
- To force black to move his king wing pawns trying to play Ka5-b6
(which would be an easy win following c6, Kxc6-d6). That can be played
with and without playing f3. I think both options win.

a) 38.Kc4 Kd8 39.Kb4 Kc7 (39...Kd7 40.Ka5 Kc7 41.f3 wins) 40.Ka5 and
white wins in all lines:
- 40...f5 41.Kb4! followed by Kc4-e5 +-
- 40...b6 41.Ka6! +-
- 40...Kb8 41.Kb6 followed by c6 +-

b) 38.f3 Kc7 39.Kc4 Kd7 40.Kb4 Kc8 41.b6! f5 42.Kc4! f4 43.Kb5! +- but
this line can be unnecesaryly complicated.

I'm wrong?

Antonio T.





 
Date: 23 Jun 2006 12:50:22
From: [email protected]
Subject: Re: pawn ending

Antonio Torrecillas wrote:
> > I examined 37 ... b6?! I can't see Black drawing unless White makes a
> > mistake. It would be close... one wrong move, and Black has a draw.
>
> After 37...b6 38.c6 is also good and do not require special precision,
> simply following Ke4, f4 and a later g5 white wins.

That makes it simple. Black's King is tied to blocking the connected
passed pawn while White's King gobbles up everything on the
kingside--minimal drawing chances.



 
Date: 21 Jun 2006 19:10:49
From: [email protected]
Subject: Re: pawn ending
Antonio Torrecillas wrote:

> a) 38.Kc4 Kd8 39.Kb4 Kc7 (39...Kd7 40.Ka5 Kc7 41.f3 wins) 40.Ka5 and
> white wins in all lines:
> - 40...f5 41.Kb4! followed by Kc4-e5 +-
> - 40...b6 41.Ka6! +-
> - 40...Kb8 41.Kb6 followed by c6 +-

Black's best defense is to delay Kc7 until White plays Ka5, preventing
a queenside invasion. But, White has a reserve tempo--f3.

38.Kc4 Kd8 39.Kb4 Kd7 40.Ka5 Kc7 41.f3

You said "White wins", but I think this is going to be close.

41. ... f5 42. Kb4 fxg4 43. fxg4 e5 44. Kc4 e4 45. Kd4 e3 46. Kxe3 Kd7
47. b6 Kc6

"White wins", as you said. I can't see a draw with best play.



 
Date: 21 Jun 2006 17:03:19
From: [email protected]
Subject: Re: pawn ending
Antonio Torrecillas wrote:
>
> White can obtain a pawn ending with 36.Bd4 Bxd4 37.Kxd4 Kd7

I examined 37 ... b6?! I can't see Black drawing unless White makes a
mistake. It would be close... one wrong move, and Black has a draw.

Line A: 36. Bd4 Bxd4 37. Kxd4 b6 38. cxb6+ Kxb6 39. Kc4 f6 40. gxf5
exf5

On the queenside, White has a clear passed pawn, which both kings are
focused on. On the kingside, Black has a pawn majority. White's king
must leave his queenside pawn to stop black's kingside pawns. Black's
best shot to draw is controlling e6/f6/g6.

41. Kd5 Kxb5 42. Ke5 f4 43. Kf5 Kc5 44. Kxg5 f3 45. Kf4 Kd5 46. Kxf3
Ke5 47. Kg4 1-0

Black loses by only one tempo! Against a lesser opponent, there are
drawing chances.

Lines B: 39. ... Kc7 40. Kc5 f5 41. b6+! Kb7 42. Kd6 Kxb6 43. Kxe6 fxg4
44. Kf5 Kc5 45. Kxg4 1-0

Line C: 39. ... Kc7! 40. Kc5 f5 41. f3? f4 42. Kd4 Kb6 43. Kc4 Kb7 44.
Kd4 Kb6 45. Kc4 Kb7 46. Kc3 Kb6 47. Kb4 e5 48. Kc4 e4 49. fxe4 f3 50.
Kd3 Kxb5 51. Ke3 Kc4 52. Kxf3 53. Kxf3 Kd4 54. e5 Kxe5 55. Ke3 1/2 -
1/2

Kc7 is an attempt to play Line A one move ahead. However, White will
still win with 41. b6+. 41. f3? is a mistake. At 1-5s per move, Rybka
chooses b6+. At 6-10s per move, it chooses f3. At 10+ seconds per move,
it chooses b6+. Again, there are real drawing chances here against a
lesser opponent.



  
Date: 23 Jun 2006 09:23:44
From: Antonio Torrecillas
Subject: Re: pawn ending
En/na [email protected] ha escrit:
> Antonio Torrecillas wrote:
>>White can obtain a pawn ending with 36.Bd4 Bxd4 37.Kxd4 Kd7
>
> I examined 37 ... b6?! I can't see Black drawing unless White makes a
> mistake. It would be close... one wrong move, and Black has a draw.
>
> Line A: 36. Bd4 Bxd4 37. Kxd4 b6 38. cxb6+ Kxb6 39. Kc4 f6 40. gxf5
> exf5 41. Kd5 Kxb5 42. Ke5 f4 43. Kf5 Kc5 44. Kxg5 f3 45. Kf4 Kd5
> 46. Kxf3 Ke5 47. Kg4 1-0
>
> Black loses by only one tempo! Against a lesser opponent, there are
> drawing chances.

After 37...b6 38.c6 is also good and do not require special precision,
simply following Ke4, f4 and a later g5 white wins.

AT



 
Date: 21 Jun 2006 15:31:45
From:
Subject: Re: pawn ending
Antonio Torrecillas wrote:
> Some days ago I proposed this game to study:
>
> [Event "Match des Legendes"]
> [Site "Porto Vecchio FRA"]
> [White "Spassky, B."]
> [Black "Karpov, Ana"]
> [Result "1-0"]
>
> 1. e4 c6 2. d4 d5 3. Nc3 dxe4 4. Nxe4 Nd7 5. Nf3 Ngf6 6. Nxf6+ Nxf6 7.h3
> Bf5 8. Bd3 Bxd3 9. Qxd3 e6 10. O-O Be7 11. c4 O-O 12. b3 c5 13. Bb2 cxd4
> 14. Rfd1 Qa5 15. Bxd4 Rfd8 16. Qe2 Qf5 17. Rd3 Qe4 18. Qxe4 Nxe4 19.Rad1
> Kf8 20. Kf1 f6 21. Be3 Rxd3 22. Rxd3 Ke8 23. Nd2 Nxd2+ 24. Rxd2 a6
> 25.Ke2 Rd8 26. Rxd8+ Kxd8 27. c5 Kd7 28. Kd3 Bd8 29. b4 Bc7 30. Kc4 h5
> 31. a4 Be5 32. b5 axb5+ 33. axb5 Kc7 34. g4 hxg4 35. hxg4 Kd7 36. f4 Bb2
> 37. f5 e5 38. Kd5 Ba3 39. g5 fxg5 40.Bxg5 Bb2 41. Bh4 Bc3 42. Bg3 1-0
>
> I wrote about the engine suggestion 28....Kc6!! and I showed some
> tactical details about it in previous messages.
>
> The second all engine suggestion was 35...g5. I think that proposition
> to be a mistake. Maybe engines can not see too far in that ending.
> I would like to add some analysis about it. Let's see!
>
> FEN:
> 8/1pk5/4pp2/1PP1b1p1/2K3P1/4B3/5P2/8 w - g6 0 36
>
> ASCII
> wKc4,Be3,Pb5,c5,f2,g4
> bKc7,Be5,Pb7,e6,f6,g5
>
> White can obtain a pawn ending with 36.Bd4 Bxd4 37.Kxd4 Kd7
> In that ending white has a passed pawn in the queen wing which can be
> used as distraction to win the game in the kings wing. The problem is
> that white king has no accesss to king wing.
>
> White has two possible ideas:
> - To open king wing with f4. The problem is that there are too many
> simplifications. I think that possibility do not work.
> - To force black to move his king wing pawns trying to play Ka5-b6
> (which would be an easy win following c6, Kxc6-d6). That can be played
> with and without playing f3. I think both options win.
>
> a) 38.Kc4 Kd8 39.Kb4 Kc7 (39...Kd7 40.Ka5 Kc7 41.f3 wins) 40.Ka5 and
> white wins in all lines:
> - 40...f5 41.Kb4! followed by Kc4-e5 +-
> - 40...b6 41.Ka6! +-
> - 40...Kb8 41.Kb6 followed by c6 +-
>
> b) 38.f3 Kc7 39.Kc4 Kd7 40.Kb4 Kc8 41.b6! f5 42.Kc4! f4 43.Kb5! +- but
> this line can be unnecesaryly complicated.
>
> I'm wrong?
>
> Antonio T.

For the convenience of readers, I have created a ChessUp diagram using
your FEN. The position after your (alternate) move of 35) ... g5 :

http://tinyurl.com/ptdkq