Trying to dissect the pawns
Let's have a look at the following position.
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| Diagram 1. White to move |
8/4k3/8/1p2Pp2/p7/P1K1P3/1P6/8 w - - 0 1
Stockfish indicates that two moves are winning:
- 1.Kd3
- 1.e4
First I try to get a global overview.. If white focuses on the left sight of the position and black on the right side, both need 8 moves to promote the pawn. This assumes no interaction between left and right.
Since both parties promote at the same time, we have to look further. What if we take only the right side into account?
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| Diagram 2. White to move |
The winning moves ar now:
- 1.Kd3
- 1.Kc4
Two remarkable things happened. We have a new winning move (1.Kc4) and a winning move (e4) has vanished.
The first is caused by the fact that in the first diagram c4 is taboo for the white king. The second is caused that the black king can walk over to the left side and assist the pawns there.
I think it is save to say that isolating pawn groups is complicating matters while having no tangible benefit to justify the attempt.
Ok back to the initial position.
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| Diagram 3. White to move |
The first question should be, what are the key squares of the black pawns? We already noticed that the immediate assault of b4 gives black a counter assault against e5.
c5, d5 and e5 are key squares of f5. For both sides pawn e5 is an obstacle. But in a different way. Black cannot make use of d6 and f6, while white cannot walk through his own pawn.
e6 and d4 are corresponding squares.
Currently, I have no satisfactory explanation why I should think about Kd3. Probably Kd4 should be avoided because it might be mined. I use "mined" and "corresponding" as if it is the same. That's the fasted way to get more clarity.
So let me try
- 1.Kd3, avoiding the mined square d4 and one step closer to pawn f5. If black answers with
- 1. ... Ke6, then it immediately comes clear why the square is mined.
- 2.Kd4 Ke7. White has conquered a key square of f5, and can keep the black king at bay while conquering it.
- 1.Kd3 Kd7 Notice how the distant opposition is irrelevant here. There are too many obstacles.
- 2.e4 ... Again, I have difficulty to explain why this move even should be considered.Other then that it is the next one in line for trial and error.
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| Diagram 4. BLACK to move |
Aha, now the mechanism becomes clear! The whole right side should result in one remote white passer. While black has the obligation to get rid of the passer, the white king runs to the black pawns on the left side and gobbles them up!
2. ... f4. Black must try to keep his pawn on the board and try to get rid of both e-pawns.
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| Diagram 5. White to move |
If white would now step on the mined square f3, it would totally turn the tables, and black would be winning! And the mechanism would be the same.
Now matters have become totally clear! If white steps on the first mined square (d4) he would be giving a half point away. But stepping on the second mined square (f3) means he would be even losing.
Conclusion
The overall method is to transform the right side into a white passer, and then eat the left pawns and promote. This is a global conceptual description.
Dissecting the pawns in a detailed way is a dangerous traject which should be avoided.
I'm a bit surprised to notice that both the treatment of Dvoretsky and of Erwin l'Ami don't mention the conceptual stuff I unearth here. They go haywire into the detailed variations though. Are/were their students so good that they already know all this conceptual stuff so they are only interested in the details?
ReplyDeleteTemposchlucker asks (rhetorically):
ReplyDeleteAre/were their students so good that they already know all this conceptual stuff so they are only interested in the details?
Dvoretsky’s students tend to be very high rated. Given that l’Ami’s wife Alina is a strong IM (with a GM norm) and a student of l’Ami, I suspect that is also true of him. Do these highly rated players already “know” ALL the conceptual stuff? Somehow, I doubt it.
How we approach a given position is definitely idiosyncratic — as has been stressed by many authors (and commentators as well); there is no “one correct way” to start the analysis process. The bottom line: begin with what makes sense to YOU.
All roads SHOULD lead to Rome!
Given the arrows, lines and numbers in Diagram 1, it is “natural” to first try to figure out what those additional items “mean.”
If I were first given the position without the additional items, I wouldn’t start by trying to figure out the result of a pawn race to promotion. My first inclination is to treat the four pawns on the queenside as balanced [2:2] while noticing that the kingside pawns are unbalanced [2:1]. The Principle of Two Weaknesses applies. My immediate concern would be how to try to get an outside passed pawn, which could then be “ditched” for Black to capture while I eliminated both Black queenside pawns. The initial goal is to use the WPe5 as a diversion of the Black king. With two White pawns left on the queenside, the win should be fairly easy.
Having gotten that idea, I would look for familiar patterns. VOILA! My favorite pawn structure (the Trébuchet, in an altered form from the canonical form) is embedded in the position. Here’s what I “SAW” as the embedded pattern:
FEN: 8/4k3/8/4Pp2/8/2K5/8/8 w - - 0 1
The e6 and d4 squares are mined. The WPe3 provides the possibility of eliminating the BPf5, preventing it from promoting, or using it for tempo gain if an actual Trébuchet occurs. The barebones Trébuchet is a draw; adding the WPe3 provides winning chances. In that modified position (with WPe3 and no queenside pawns), Kc4 and Kd3 both win. As you noted, Kc4 is eliminated by the BPb5 in Diagram 1; that only leaves Kd3 as a winning attempt.
That “analysis” provides a conceptual framework, simplifying the “planning” of the move sequences. At this point, the concrete details must be investigated move-by-move, and the numerous pitfalls identified and avoided.
I may be delusional as to what I "SEE".
Thanks! The fact that I managed to throw away 5 x 0.5 points in 5 endgames against opposition which was only 100 rating points higher already seemed to indicate that my conceptual knowledge of the endgame is far below average. And it feels that way.
DeleteLuckily it seems to be fixable. It is only a lot of work.
I have now a clear picture of what must be done and how to do it. When I tried my hand with endgames for the first time in 2006, I had not the slightest idea what I was looking for.
Delete