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Desmond
14-12-2009, 07:20 PM
Can white win this?

8/p3k1p1/1p2pp1p/P2bP3/1P1K1P2/3B2P1/7P/8 w - - 0 1

Spiny Norman
14-12-2009, 07:39 PM
I don't think so. As long as Black doesn't do anything really stupid ...

Capablanca-Fan
14-12-2009, 08:06 PM
Black has a bad B, but his Q-side Ps are well placed to complement it.

Try h4, with ideas of exf6:
if ... gxf6, then g4-g5 makes an outside passed P. This should have serious winning chances.
if ... Kxf6, then g4-g5 will clear e5 for White's K. That's progress, but Black would have only one weakness.

Desmond
14-12-2009, 08:20 PM
Thanks Jono. I tried chopping on b6 and bringing my king to b5 but he brought his King over to c7 in time and I couldn't do much there.

At some point he played ...f5 which looked ugly but I couldn't work out how to take advantage. I tried a couple of cheapies with overworking the e6 pawn (Bxf5 Kxd5) but he didn't give me the chance.

As you say, the one weakness didn't seem to be enough to win.

MichaelBaron
17-12-2009, 11:10 AM
Its a bit better for white but draw is the most likely result

Kevin Bonham
17-12-2009, 10:57 PM
I'd be interested to know what people think of this:

8/1b3pk1/p2p4/1p1P4/5K1P/1B6/PP6/8 b - - 0 1

Black to move. Obviously one I would rather be white than black but how uneven is it?

+/=, +/- or +- ?

Carl Gorka
17-12-2009, 11:16 PM
I'd be interested to know what people think of this:

8/1b3pk1/p2p4/1p1P4/5K1P/1B6/PP6/8 b - - 0 1

Black to move. Obviously one would rather be white than black but how uneven is it?

+/=, +/- or +- ?

Why is white obviously better?

Desmond
17-12-2009, 11:25 PM
At a glance, I think white is winning that. He should be able to use the h-pawn as a decoy for the black king and mop up with his own king.

Carl Gorka
17-12-2009, 11:33 PM
At a glance, I think white is winning that. He should be able to use the h-pawn as a decoy for the black king and mop up with his own king.

How is white's king going to penetrate after say 1..Bc8? Or 1..a5 2.a3 b4 when Black's bishop can shuffle between the f1-a6 diagonal and the h3-c8 diagonal?

Kevin Bonham
17-12-2009, 11:36 PM
Why is white obviously better?

To me, black has obvious problems because white has an outside passed pawn and a favourable king position, especially relevant because if black's king diverts to stop white's pawn then white will get in towards the very weak black pawn on d6.

It's true that white's d5-pawn is currently a burden, but it only really remains so while the black bishop attacks it and sort-of ties the white bishop to a fairly boring diagonal, thus rendering itself completely passive in the process. And the black bishop can't just sit there attacking the d5-pawn forever, or white will win much as if it was a straight king and pawn ending with the bishops off the board.

So as I see it black clearly has issues to deal with (which is not to say they can't be dealt with) while white has no problems that actually matter and therefore white must be "better" in practical terms whether or not it is objectively a draw.

But if anyone wants to disagree with that I'll gladly put a strikethrough through my "obviously". :lol:

Carl Gorka
17-12-2009, 11:54 PM
To me, black has obvious problems because white has an outside passed pawn and a favourable king position, especially relevant because if black's king diverts to stop white's pawn then white will get in towards the very weak black pawn on d6.

I'm not sure how white's king is going to penetrate into the black position. Black's king doesn't have to divert to stop the h-pawn, it is in perfect position to do so, and should white sac it, then black's king is in good position to support his own passed f-pawn.


It's true that white's d5-pawn is currently a burden, but it only really remains so while the black bishop attacks it and sort-of ties the white bishop to a fairly boring diagonal, thus rendering itself completely passive in the process. And the black bishop can't just sit there attacking the d5-pawn forever, or white will win much as if it was a straight king and pawn ending with the bishops off the board.

White's d-pawn is a permanent weakness which will always need to be thought about. Black's bishop seems passive but it is attacking at the moment whereas white's is the defending piece. Should Black's bishop seek some open lines, then it is a move away from attacking the d-pawn so unless white can generate a position where he is willing to dump his d-pawn then one of his pieces will be tied to its defence.


So as I see it black clearly has issues to deal with (which is not to say they can't be dealt with) while white has no problems that actually matter and therefore white must be "better" in practical terms whether or not it is objectively a draw.

I think its level, but if either side tries too hard to win, they run the risk of dropping into a worse position


But if anyone wants to disagree with that I'll gladly put a strikethrough through my "obviously". :lol:

Kevin Bonham
18-12-2009, 12:48 AM
I've disposed of my "obviously" but I'd still rather be white. :lol:

One thing I have noticed is that sooner or later black will probably play ...f6, and then white will be trying to acheive Kf5-e6 winning. For instance 1...a5 2.a3 b4 3.Kg5 and black is going to have to play ...f6 soon or white will have a win after h5, h6, Kf6 etc with Bc2 thrown in where needed; some version or other of this seems to work wherever black's bishop is.

Once ...f6 is played I reckon fireeater is right that just switching the black bishop between the two diagonals (not from move to move but simply as required) , if done even remotely carefully, stops white ever getting through.

After 1...a5 White can play 2.Ke4 but now black seems to get away with ...Kg6 then ...f5.

I was curious about this one because I did actually win it with white after black made some bad errors (like leaving the queenside pawns on light squares where they are both weaker and in the way), and I wanted to see what a clearcut holding plan for black actually might be (if there was one).

This is what happened:

1...Kf6 2.a3 Bc8 3.Bc2 Bh3 4.Be4 Bf1 5.h5 Kg7 6.Kg5 f6+ 7.Kf4 [7.Kg4 looks clearer] 7...Be2 [7...Bh3 8.b4] 8.Kf5 Bxh5 9.Ke6 Bg4+ 10.Kxd6 f5 11.Bg2 Kf6 12.Kc7 f4 13.d6 Ke5 14.b4 Kd4 15.d7 Bxd7 16.Kxd7 Kc3 17.Kd6 Kb3 18.Kc5 Kxa3 19.Bb7 ... 1-0

Spiny Norman
18-12-2009, 04:46 AM
I'm not convinced about Black's starting plan (1...Kf6 and 2..Bc8). I think the position is finely balanced, with White's outside passed pawn giving him an edge, however White's bishop is quite passive. If I'm Black, I think I would try 1...a4, threatening to kick the bishop from its defensive duties protecting the e-pawn. If White responds with 2.Ke4 then I'd play 2...b4

At that point I have achieved a number of things:
(1) my q-side pawns are now on black squares, making them invulnerable to attach from the White bishop; and
(2) the White king cannot penetrate the q-side because of Ba6
(3) if White tries to swap off the bishops in order to get in on the q-side, Black will mop up the h-pawn and queen his f-pawn before White can achieve anything

I'd feel fairly confident of holding that position as Black. Of course, my confidence could be badly misplaced!

Desmond
18-12-2009, 08:21 AM
How is white's king going to penetrate after say 1..Bc8? Or 1..a5 2.a3 b4 when Black's bishop can shuffle between the f1-a6 diagonal and the h3-c8 diagonal?
Well for a start black can probably not afford to swap bishops in most lines since the reulting pawn ending with outside passer will almost always be lost for him. So white can oppose bishops at moments when it suits.

Carl Gorka
18-12-2009, 10:44 AM
I'm not convinced about Black's starting plan (1...Kf6 and 2..Bc8). I think the position is finely balanced, with White's outside passed pawn giving him an edge, however White's bishop is quite passive. If I'm Black, I think I would try 1...a4, threatening to kick the bishop from its defensive duties protecting the e-pawn. If White responds with 2.Ke4 then I'd play 2...b4

At that point I have achieved a number of things:
(1) my q-side pawns are now on black squares, making them invulnerable to attach from the White bishop; and
(2) the White king cannot penetrate the q-side because of Ba6
(3) if White tries to swap off the bishops in order to get in on the q-side, Black will mop up the h-pawn and queen his f-pawn before White can achieve anything

I'd feel fairly confident of holding that position as Black. Of course, my confidence could be badly misplaced!

after 1.a4, white can play 2.Bc4. 2.Ke4 loses a piece. If black continues 1..a4 2.Bc4 b5, then White just takes on b5, then on a4 with passed pawns on both sides of the board which is probably a win.

Carl Gorka
18-12-2009, 10:47 AM
Well for a start black can probably not afford to swap bishops in most lines since the reulting pawn ending with outside passer will almost always be lost for him. So white can oppose bishops at moments when it suits.

Agreed, Black will not swap bishops until things have settled, but I don't see how this will help White's king to penetrate the black position. If white's king cannot attack black's pawns, then he can't win, but in trying to infiltrate with his king, white will have to offer some of his own pawns and this seems to me to be an unnecessary risk.

Kevin Bonham
18-12-2009, 12:14 PM
Well for a start black can probably not afford to swap bishops in most lines since the reulting pawn ending with outside passer will almost always be lost for him. So white can oppose bishops at moments when it suits.

This is why fireeater's second plan of creating a second diagonal for the bishop to work on by playing ...a5 and ...b4 right away appears to be such a good one. Again envisaging a position with a black pawn on f6, white can easily boot the black bishop off the h3-c8 diagonal. But then if it goes to the f1-a6 diagonal, it can attack the white d-pawn from behind on that diagonal. White won't make progress if the king is guarding that pawn from behind. If the bishop guards it from e6 thus keeping the black bishop off the first diagonal, then white would like to play Kf5 and push the h-pawn but the bishop checks black's king away from behind - and it can't go to e6 because the bishop is in the way. If white drops the bishop back to e4 then it is no longer blocking the first diagonal, and black has time to drop the bishop back to a6 then meet Kf5 with ...Bc8+ and the white king is kept out again. Everything keeps not quite working.

Something I did find in some lines was that white could let the d-pawn go, and after swapping the h-pawn for the f-pawn by pushing the h-pawn could then clean up both black's d-pawn and eventually black's b-pawn. But the resulting KBP vs KB is a draw; also, it doesn't look like white can force a position where this works.

Igor_Goldenberg
19-12-2009, 06:21 PM
I suggest 1... Kg6.
To defend (black does need to defend due to distant passed pawn and more active white king) black needs to keep king on h6 (preventing white king from venturing to g5 and threatening h pawn) and bishop on c8. If white plays Bf5 then black bishop returns to b7 attacking d5 pawn. Black should avoid playing f6 (as white can play Be6, swap f6 pawn for h4 and attack queen side).
1... Bc8 allows 2.Kg5, 1...Kh6 allows 2.Kf5, hence 1...Kg6. If 2.Bc2+ Kh6, and white cannot play 3.Kf5 (d5 pawn is en prise).
white must guard h5 square, so zugswang is not possible.

White can try to put bishop on f3 and try marching to queen side, but black can counter but activating king through g6-f5.

I think it should be a draw.