5K2/2p5/8/2k5/8/2P5/4P3/8 w - - 0 1
Yancey, I studied your positions and I understood the difference between them. In the first variation the white queen could move to g5 with the check and in the second variation couldn't. The king blocked the way. Qg5 was the only move to win in the first variation.
Here are the two critical positions: 4Q3/8/5K2/8/8/2p5/3k4/8 w - - 0 1 and 4Q3/5K2/8/8/8/2p5/3k4/8 w - - 0 1. The first is a draw with best play, the second is a win for white with best play. Why?
Yes, but what was the critical difference- why did the pawn reach c2 in one line and not the other?
I considered your two lines 1.Kg7 Kd5 2.Kf7 and 1.Kf7 Kd5 2.Kf6.
They look similiar but they don't. In this varition 1.Kf7 Kd5 2.Kf6 only a draw because the black pawn reached c2. On the other hand in this varition 1.Kg7 Kd5 2.Kf7 the black pawn didn't reach c2 and it's a win. Although in both varitions the white queen on e8.
I meant, "where white has queened at e8". Alena, open this thread for an important message.
Alena, open this thread up to seen an important message.
The difference is incredibly subtle and is the entire point of Zinar's puzzle.
To find the problem, you will have to go several moves beyond those two lines where white has queened at d8. What you will find are two positions that look almost identical, but, very, very countintuitively, one is winning for white while the other isn't.
The first part of the last paragraph is completely correct about 1.Ke7, but I don't think the second part really describes the problem that white creates for himself with 1.Kf7. What I would suggest, Alena, is to carefully study the lines that start with 1.Kg7 Kd5 2.Kf7 and compare them to the line that starts 1.Kf7 Kd5 2.Kf6. The problem isn't that white loses both pawns, but that queening the e-pawn in the latter position doesn't lead to a win, but that he is still one tempo ahead in the first line, which makes all the difference in the world.
It's a win for white.
It's a win for white.
Ke7 loses because it's on the same file as the white pawn. Therefore white loses an important tempo and black has time to put the black pawn on c2. Kf7 and e4 loses too because black gets the opposition and controls white pawns.