Daily Chess Improvement: Endgame Accuracy!
SusanPolgar
White to move! How should white proceed? Write out the solution please!
SusanPolgar
White to move! How should white proceed? Write out the solution please!
This is a very good exercise in tempo-counting, which is something I have to write down to get.
We can see that W's goal is to clean up the queenside and get to b7 before B can take his kingside pawn and get to c8. B has to lose 3 tempi (b5, bxa4 and b3). W has to lose two (bxa3 and the initial capture on g5). It will take B a minimum of 6 K tempi to capture a pawn on the g file and get to c8. Two more if the pawn is on the h file. It will take W a minimum of 7 K tempi to get from the f file to the b7 after cleaning up. 8 if he starts from g5. Arithmetically, hxg5 results in W needing 7+2 = 9 tempi and B 6+3=9 tempi. Similarly, Kxg5 results in W needing 8+2 = 10 tempi and B 8+3=11. Naively, either should therefore result in a W win (though Kg5 gives more margin)
Let's look at hxg5 and see if the arithmetic adds up
So lets see if we can do better by not moving the pawn,
Compare to Yancey's line above
Can black do better? If he tries to deny W the d6 square, perhaps?
Now if I could do this mentally, I'd actually be able to play these on the board :-)
Editor
The problem for white is going to be black exchanging down on the queen side with b5, leaving white with, at best a rook's pawn on the a-file or creating his own passed pawn. First principles here would suggest white needs to drive the black king as far away as possible from the queen side corner at a8, so this means white should capture at g5 with the king, not the pawn- it threatens to queen the h-pawn if the black king doesn't respond:
1.Kxg5
White is now threatening to play 2.Kg6 followed by a queen on move 6. Black doesn't have time to creat a passed pawn on the queenside- for example
1.Kg5 b5 2.Kg6 ba4 3.h5 a3 4.ba3 c5 5.h6 c4 6.h7 c3 7.h8(Q) wins.
So, after 1.Kg5, black must try to stop the h-pawn:
1.Kg5 Kf6 2.Kf5
There are probably lots of winning moves for white at move 2, but 2.Kf5 seems simplest to me- white is setting the king on the journey to the queenside- the pawn on h4 is just fine- the black king can't leave it and must go capture it, taking him far from the a8 corner. However, I can see one last trick in this position.....
2......b5! 3.Ke5 ba4 4.Kd6 Kg6 5.Kc6 Kh5 6.Kb5 a3 7.ba3 Kh4 8.Ka5 wins
And I am pretty sure that 3.axb5 is a mistake that costs the win- I don't see how white prevents black from exchanging off both white pawns after that point.