Is this ending winnable?

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Date: 06 Feb 2006 20:28:47
From: Major Cat
Subject: Is this ending winnable?

K & P's vs. K & P's ending:

8/6p1/5p1p/ppk5/8/P1Pp1P1P/1P3KP1/8 w - -

Material is even.

Is this ending winnable for either side? If so, I have
not been able to demonstrate it! 8 >)

Thanks in advance.

Date: 08 Feb 2006 06:12:55
From: Alan Watts
Subject: Re: Is this ending winnable?

Major Cat <[email protected] > wrote in news:[email protected]:

> 8/6p1/5p1p/ppk5/8/P1Pp1P1P/1P3KP1/8 w - -
>

Here is how ChessGenius played it out - White wins.

[Event "newsgroup"]
[Site "?"]
[Date "0000.??.??"]
[Round "?"]
[White ""]
[Black ""]
[Result "1-0"]
[FEN "8/6p1/5p1p/ppk5/8/P1Pp1P1P/1P3KP1/8 w - -"]

1. b3 b4 2. axb4+ axb4 3. Ke3 bxc3 4. Kxd3 Kb4 5. Kc2 f5 6. f4 g5 7. g3
gxf4
8. gxf4 h5 9. h4 Kc5 10. Kxc3 Kd5 11. b4 Ke4 12. b5 Kd5 13. Kb4 Ke4 14. b6
Kxf4 15. b7 Kg4 16. b8=Q f4 17. Kc4 f3 18. Kd3 Kf5 19. Ke3 Kg6 20. Qe5 Kf7
21.
Qxh5+ Kf6 22. Qxf3+ Ke6 23. Kd4 Kd7 24. Qf6 Kc8 25. Kc5 Kb8 26. Qf7 Kc8 27.
Kc6 Kd8 28. Qd7+ 1-0

Date: 08 Feb 2006 03:02:36
From: Major Cat
Subject: Re: Is this ending winnable?

Alan Watts wrote:
>
> Major Cat <[email protected]> wrote in news:[email protected]:
>
> > 8/6p1/5p1p/ppk5/8/P1Pp1P1P/1P3KP1/8 w - -
> >
>
> Here is how ChessGenius played it out - White wins.

Thanks for taking the time to look over the ending.

>
> [Event "newsgroup"]
> [Site "?"]
> [Date "0000.??.??"]
> [Round "?"]
> [White ""]
> [Black ""]
> [Result "1-0"]
> [FEN "8/6p1/5p1p/ppk5/8/P1Pp1P1P/1P3KP1/8 w - -"]
>
> 1. b3 b4

This is where the program went astray as per Claus-Juergen's
analysis. He wrote:

"The attack 1...b4 loses also: 2. axb4! axb4 3. Ke3! bxc3
4. Kxd3 Kb4 5. Kc2 mutual Zugzwang but Black is to move first
and loses the tempo fight.

> 2. axb4+ axb4 3. Ke3 bxc3 4. Kxd3 Kb4 5. Kc2

Claus-Juergen and ChessGenius are in complete agreement! 8 >)

> f5 6. f4 g5 7. g3 gxf4
> 8. gxf4 h5 9. h4 Kc5 10. Kxc3 Kd5 11. b4 Ke4 12. b5 Kd5 13. Kb4 Ke4 14. b6
> Kxf4 15. b7 Kg4 16. b8=Q f4 17. Kc4 f3 18. Kd3 Kf5 19. Ke3 Kg6 20. Qe5 Kf7
> 21. Qxh5+ Kf6 22. Qxf3+ Ke6 23. Kd4 Kd7 24. Qf6 Kc8 25. Kc5 Kb8 26. Qf7 Kc8
> 27. Kc6 Kd8 28. Qd7+ 1-0

Date: 08 Feb 2006 07:43:43
From: John J.
Subject: Re: Is this ending winnable?

1....a4 is essential for the draw.

"Alan Watts" <[email protected] > wrote in message
news:[email protected]...
> Major Cat <[email protected]> wrote in news:[email protected]:
>
>> 8/6p1/5p1p/ppk5/8/P1Pp1P1P/1P3KP1/8 w - -
>>
>
>
>
> Here is how ChessGenius played it out - White wins.
>
> [Event "newsgroup"]
> [Site "?"]
> [Date "0000.??.??"]
> [Round "?"]
> [White ""]
> [Black ""]
> [Result "1-0"]
> [FEN "8/6p1/5p1p/ppk5/8/P1Pp1P1P/1P3KP1/8 w - -"]
>
> 1. b3 b4 2. axb4+ axb4 3. Ke3 bxc3 4. Kxd3 Kb4 5. Kc2 f5 6. f4 g5 7. g3
> gxf4
> 8. gxf4 h5 9. h4 Kc5 10. Kxc3 Kd5 11. b4 Ke4 12. b5 Kd5 13. Kb4 Ke4 14. b6
> Kxf4 15. b7 Kg4 16. b8=Q f4 17. Kc4 f3 18. Kd3 Kf5 19. Ke3 Kg6 20. Qe5 Kf7
> 21.
> Qxh5+ Kf6 22. Qxf3+ Ke6 23. Kd4 Kd7 24. Qf6 Kc8 25. Kc5 Kb8 26. Qf7 Kc8
> 27.
> Kc6 Kd8 28. Qd7+ 1-0

Date: 07 Feb 2006 04:13:30
From: =?ISO-8859-1?Q?Claus-J=FCrgen_Heigl?=
Subject: Re: Is this ending winnable?

Major Cat wrote:
> K & P's vs. K & P's ending:
>
> 8/6p1/5p1p/ppk5/8/P1Pp1P1P/1P3KP1/8 w - -
>
> Material is even.
>
> Is this ending winnable for either side? If so, I have
> not been able to demonstrate it! 8>)

It's a draw but Black has to be very careful.

1. b3

This is a must, otherwise the black king intrudes to b3 and captures the
white pawns.

1...a4!

If Black touches king or kingside pawns White plays Ke3 and wins d3 and
the game. The attack 1...b4 loses also: 2. axb4! (2. cxb4? axb4 3. a4
(3. axb4 Kxb4 4. Ke3 Kc3! -+) 3...Kd4 4. Ke1 Kc3 5. Kd1 Kxb3 and
although White queens first Black moves in with mate.) 2...axb4 3. Ke3!
bxc3 4. Kxd3 Kb4 5. Kc2 mutual Zugzwang but Black is to move first and
loses the tempo fight.

2. bxa4 bxa4 3. Ke3 Kc4 4. Kd2 Kb3 5. Kxd3 Kxa3 6. Kc2

Now Black has to exhaust his moves on the kingside.

6...h5 7. h4 (f4 or g3 make no difference, other moves lose) 7...g5 8.
g3 gxh4 9. gxh4 f5 10. f4 Ka2 11. c4 a3 12. c5 Ka1 13. c6 a2 14. c7
stalemate.

Claus-Juergen

Date: 08 Feb 2006 00:32:38
From: bruno de baenst
Subject: Re: Is this ending winnable?

"Claus-J�rgen Heigl" <[email protected] > schreef in bericht
news:[email protected]...
> Major Cat wrote:
>> K & P's vs. K & P's ending:
>>
>> 8/6p1/5p1p/ppk5/8/P1Pp1P1P/1P3KP1/8 w - -
>>
>> Material is even.
>>
>> Is this ending winnable for either side? If so, I have
>> not been able to demonstrate it! 8>)
>
> It's a draw but Black has to be very careful.
>
> 1. b3
>
> This is a must, otherwise the black king intrudes to b3 and captures the
> white pawns.
>
> 1...a4!
>
> If Black touches king or kingside pawns White plays Ke3 and wins d3 and
> the game.

I don't think that's true h5 and f5 also seems to hold :
for example : 1.b3 h5 2.Ke3 a4 3.bxa4 Kc4 4.Kd2 [4.axb5 Kxc3 5.b6 d2 6.b7
d1Q 7.b8Q draw] 4...bxa4 with draw similar to your line.

Date: 08 Feb 2006 12:58:13
From: =?ISO-8859-1?Q?Claus-J=FCrgen_Heigl?=
Subject: Re: Is this ending winnable?

bruno de baenst wrote:
> "Claus-J=FCrgen Heigl" <[email protected]> schreef in bericht=20
> news:[email protected]...
>>
>>If Black touches king or kingside pawns White plays Ke3 and wins d3 and=
=20
>>the game.
>=20
> I don't think that's true h5 and f5 also seems to hold :
> for example : 1.b3 h5 2.Ke3 a4 3.bxa4 Kc4 4.Kd2 [4.axb5 Kxc3 5.b6 d2 6.=
b7=20
> d1Q 7.b8Q draw] 4...bxa4 with draw similar to your line.

Yes, you are right. The difference is that White could try his luck in a =

queen ending that should be drawn because the White king can't get to=20
the black pawns.

4. axb5 Kxc3 5. b6 d2 6. b7 d1Q 7. b8Q Qd2+ 8. Ke4 Qxg2 9. Qb4+ Kc2 10.=20
Qc5+ Kb3 11. Qxh5 Qe2+ 12. Kf5 (12. Kd4 Qd2+ 13. Kc5?? Qa5+; 12. Kf4 g5+ =

13. Kf5 Qe5+ 14. Kg6 Qe8+ 15. Kh6 Qh8+) 12...Qe5+ 13. Kf4 (13. Kg6??=20
Qe8+) 13...Qd4+ and White can't escape the checks.

Your line proves that one should be very careful when analysing a pawn=20
endgame.

Claus-Juergen

Date: 08 Feb 2006 03:15:37
From: Major Cat
Subject: Re: Is this ending winnable?

bruno de baenst wrote:
>
> "Claus-J�rgen Heigl" <[email protected]> schreef in bericht
> news:[email protected]...
> > Major Cat wrote:
> >> K & P's vs. K & P's ending:
> >>
> >> 8/6p1/5p1p/ppk5/8/P1Pp1P1P/1P3KP1/8 w - -
> >>
> >> Material is even.
> >>
> >> Is this ending winnable for either side? If so, I have
> >> not been able to demonstrate it! 8>)
> >
> > It's a draw but Black has to be very careful.
> >
> > 1. b3
> >
> > This is a must, otherwise the black king intrudes to b3 and captures the
> > white pawns.
> >
> > 1...a4!
> >
> > If Black touches king or kingside pawns White plays Ke3 and wins d3 and
> > the game.
>
> I don't think that's true h5 and f5 also seems to hold :
> for example : 1.b3 h5 2.Ke3 a4 3.bxa4 Kc4 4.Kd2 [4.axb5 Kxc3 5.b6 d2 6.b7
> d1Q 7.b8Q draw] 4...bxa4 with draw similar to your line.

In a post subsequent to the one containing the analysis that
you have commented upon, Claus-Juergen allowed for some
flexibility in regards to the timing of dissipation of K-side
tempi.

Your analysis would suggest the following line of play as an
interesting alternative:

1. b3 a4 2. bxa4 Kc4 ?! 3. axb5 Kxc3 4. b6 d2 5. b7 d1=Q 6. b8=Q

My preference here would be to play the white pieces... 8 >)

Date: 07 Feb 2006 16:47:09
From: Antonio Torrecillas
Subject: Re: Is this ending winnable?

En/na Claus-J�rgen Heigl ha escrit:

> Major Cat wrote:
>> 8/6p1/5p1p/ppk5/8/P1Pp1P1P/1P3KP1/8 w - -
>>
>> Material is even.
>>
>> Is this ending winnable for either side? If so, I have
>> not been able to demonstrate it! 8>)
>
> It's a draw but Black has to be very careful.
> (...)
>
> Claus-Juergen

Great analysis Claus-Juergen!! thanks

I ask me if black would have won with his h6 pawn in h7 (or his f6 pawn
in f6). It seems we achieve the same final zugwang position (Kc4 vs Kd2)
and here white has top move and loses.

The FEN for those two positions are:

8/6pp/5p2/ppk5/8/P1Pp1P1P/1P3KP1/8 w - -

8/5pp1/7p/ppk5/8/P1Pp1P1P/1P3KP1/8 w - -

AT

Date: 07 Feb 2006 18:18:49
From: =?ISO-8859-1?Q?Claus-J=FCrgen_Heigl?=
Subject: Re: Is this ending winnable?

Antonio Torrecillas wrote:
> I ask me if black would have won with his h6 pawn in h7 (or his f6 pawn
> in f6). It seems we achieve the same final zugwang position (Kc4 vs Kd2)
> and here white has top move and loses.
>
> The FEN for those two positions are:
>
> 8/6pp/5p2/ppk5/8/P1Pp1P1P/1P3KP1/8 w - -
> 8/5pp1/7p/ppk5/8/P1Pp1P1P/1P3KP1/8 w - -

Hello Antonio,

I agree. If Black has another reserve tempo on the kingside, White loses
the tempo fight and can't defend the queenside.

8/5pp1/7p/ppk5/8/P1Pp1P1P/1P3KP1/8 w - -

1. b3 a4 2. bxa4 bxa4 3. Ke3 Kc4 4. Kd2 h6 (in the position with the
pawn on f7 Black plays f6) 5. h4 h5 6. g4 g6 7. gxh5 ghx5 8. f4 f5 9.
Kd1 Kxc3 and Black wins.

Greetings

Claus-Juergen

Date: 07 Feb 2006 02:07:32
From: Major Cat
Subject: Re: Is this ending winnable?

Thank you very much for taking the time to look over this ending.
As usual, your analysis is very thorough! 8 >) I have inserted my
comments on specifics below.

Claus-J�rgen Heigl wrote:
>
> Major Cat wrote:
> > K & P's vs. K & P's ending:
> >
> > 8/6p1/5p1p/ppk5/8/P1Pp1P1P/1P3KP1/8 w - -
> >
> > Material is even.
> >
> > Is this ending winnable for either side? If so, I have
> > not been able to demonstrate it! 8>)
>
> It's a draw but Black has to be very careful.

White has to be a tad careful too...

>
> 1. b3
>
> This is a must, otherwise the black king intrudes to b3 and captures the
> white pawns.

Done exactly that!

>
> 1...a4!

My opponent also did as you suggest.

>
> If Black touches king or kingside pawns White plays Ke3 and wins d3 and
> the game. The attack 1...b4 loses also: 2. axb4! (2. cxb4? axb4 3. a4
> (3. axb4 Kxb4 4. Ke3 Kc3! -+) 3...Kd4 4. Ke1 Kc3 5. Kd1 Kxb3 and
> although White queens first Black moves in with mate.) 2...axb4 3. Ke3!
> bxc3 4. Kxd3 Kb4 5. Kc2 mutual Zugzwang but Black is to move first and
> loses the tempo fight.
>
> 2. bxa4 bxa4 3. Ke3 Kc4 4. Kd2

Up to this point, the actual game unfolded as per your suggestions.
My opponent, then, moved to exhaust his moves on the K-side. Only
when he accomplished that did he play ...Kb3.

> 4...Kb3 5. Kxd3 Kxa3 6. Kc2
>
> Now Black has to exhaust his moves on the kingside.
>
> 6...h5 7. h4 (f4 or g3 make no difference, other moves lose) 7...g5 8.
> g3 gxh4 9. gxh4 f5 10. f4

The game actually ended as per your following suggestions:

> 10...Ka2 11. c4 a3 12. c5 Ka1 13. c6 a2 14. c7
> stalemate.

Both my opponent and myself wondered how "intuitive" all this
is supposed to be! 8 >)

Date: 07 Feb 2006 02:55:53
From: John J.
Subject: Re: Is this ending winnable?

Black wins easy. Just think abouit it in military terms. :)
"Major Cat" <[email protected] > wrote in message
news:[email protected]...
>K & P's vs. K & P's ending:
>
> 8/6p1/5p1p/ppk5/8/P1Pp1P1P/1P3KP1/8 w - -
>
> Material is even.
>
> Is this ending winnable for either side? If so, I have
> not been able to demonstrate it! 8>)
>
> Thanks in advance.
>

Date: 07 Feb 2006 01:09:21
From: Major Cat
Subject: Re: Is this ending winnable?

John J. wrote:
>
> Black wins easy. Just think abouit it in military terms. :)

I see that you do not intend to drop the "subject". Very well,
then. In military history terms, I associate "Black" with the
fascist "Blackshirts" and the nazi "SS". They may have won some
battles but not the war...

Date: 07 Feb 2006 01:47:37
From: Ron
Subject: Re: Is this ending winnable?

In article <[email protected] >, Major Cat <[email protected]>
wrote:

> 8/6p1/5p1p/ppk5/8/P1Pp1P1P/1P3KP1/8 w - -
>
> Material is even.
>
> Is this ending winnable for either side? If so, I have
> not been able to demonstrate it! 8>)

This looks good for black, although I haven't looked at it long enough
to see if white has a defense.

Black's strategy is simple: he will advance the king to b3, trading the
d-pawn for the a & b pawns. White's only way to stop the a-pawn will be
to keep the black king on the a-file in front of it, by keeping the
opposition horizontally.

So it becomes race to see who can lose more pawn moves on the kingside.
Black is aiming for a position with his king on a2, pawn on a3 with
white to move. Then Kc1 allows Kb3 and the black king eats the kingside
pawns, or Kc3 Kb1 and the a-pawn queens.

I always screw up those "who can lose more moves before the pawns are
locks" races, so I wouldn't be surprised if I have this one wrong, too.
But I think black's holding all the cards here.

-Ron

Date: 07 Feb 2006 02:51:53
From: Major Cat
Subject: Re: Is this ending winnable?

Ron wrote:
>
> In article <[email protected]>, Major Cat <[email protected]>
> wrote:
>
> > 8/6p1/5p1p/ppk5/8/P1Pp1P1P/1P3KP1/8 w - -
> >
> > Material is even.
> >
> > Is this ending winnable for either side? If so, I have
> > not been able to demonstrate it! 8>)
>
> This looks good for black,

That is what I thought while playing white...

> although I haven't looked at it long enough
> to see if white has a defense.

Your contribution is much appreciated.

>
> Black's strategy is simple: he will advance the king to b3,

The timing of this advance seems to be critical.

> trading the
> d-pawn for the a & b pawns.

Actually, as per Claus-Juergen's analysis and the way the actual
game went, the b-pawns are (were) exchanged before the Black K's
advance to b3.

> White's only way to stop the a-pawn will be
> to keep the black king on the a-file in front of it, by keeping the
> opposition horizontally.

Yes, this is an important element here. However, Black must also
guard against a promotion run by White's otherwise unobstructed
c-pawn.

>
> So it becomes race to see who can lose more pawn moves on the kingside.

The proper timing for Black to exhaust his K-side pawn moves
(tempi) is not clear to me. In the actual game, my opponent ac-
complished it before advancing his Black K to b3. Claus-Juergen's
analysis seems to suggest the opposite timing sequence.

> Black is aiming for a position with his king on a2, pawn on a3 with
> white to move. Then Kc1 allows Kb3 and the black king eats the kingside
> pawns, or Kc3 Kb1 and the a-pawn queens.

The spoiler for Black is White's c-pawn! 8 >) But, then, again,
White's spoiler in regards to that pawn's potential promotion
is a rather piquant stalemate situation...

>
> I always screw up those "who can lose more moves before the pawns are
> locks" races,

Like so many of us out there in cafes... 8 >)

> so I wouldn't be surprised if I have this one wrong, too.
> But I think black's holding all the cards here.

Let us wait and see what other posters think.

Date: 07 Feb 2006 13:48:19
From: =?ISO-8859-1?Q?Claus-J=FCrgen_Heigl?=
Subject: Re: Is this ending winnable?

Major Cat wrote:
> Ron wrote:

> The proper timing for Black to exhaust his K-side pawn moves
> (tempi) is not clear to me. In the actual game, my opponent ac-
> complished it before advancing his Black K to b3. Claus-Juergen's
> analysis seems to suggest the opposite timing sequence.

There is some leeway as to when Black has to exhaust his kingside moves.
It has to happen while Black has the c-pawn under his control. A
sequence like

1. b3 a4 2. bxa4 bxa4 3. Ke3 Kc4 4. Kd2 h5 (or f5, but beware of 4...g6?
5. f4 g5 (5...f5 6. h4) 6. fxg5 followed by g4) 5. h4 g5 6. g3 Kb3 7.
Kxd3 Kxa3 8. Kc2 gxh4

and so on is also possible.

Claus-Juergen

Date: 07 Feb 2006 14:56:55
From: Major Cat
Subject: Re: Is this ending winnable?

Many thanks for the additional analysis.

Claus-J�rgen Heigl wrote:
> > The proper timing for Black to exhaust his K-side pawn moves
> > (tempi) is not clear to me. In the actual game, my opponent ac-
> > complished it before advancing his Black K to b3. Claus-Juergen's
> > analysis seems to suggest the opposite timing sequence.
>
> There is some leeway as to when Black has to exhaust his kingside moves.
> It has to happen while Black has the c-pawn under his control. A
> sequence like
>
> 1. b3 a4 2. bxa4 bxa4 3. Ke3 Kc4 4. Kd2 h5 (or f5, but beware of 4...g6?
> 5. f4 g5 (5...f5 6. h4) 6. fxg5 followed by g4) 5. h4 g5 6. g3 Kb3 7.
> Kxd3 Kxa3 8. Kc2 gxh4
>
> and so on is also possible.
>
> Claus-Juergen