Dennis M's Chess Site

This is a blog for chess fans by a chess fan. I enjoy winning as much as anyone else, and I've had a reasonable amount of success as a competitor, but what keeps me coming back to the game is its beauty. And that, primarily, is what this site will be about! All material copyrighted.

Thursday, February 17, 2005

King and Pawn Endings, Part Six

A few days ago, I offered this amazing position as a challenge to the readers:

Laveryd-Wikstrom, Umea 1997. Black to move; what should the result be?

On the queenside, the two kings are in a mutual zugzwang, so it would certainly appear to come down to tempo play on the kingside. If it were just a matter of the g- and h-pawns, White would simply copy Black's play, Black would run out of moves, and that would apparently be that. However, the f- and especially the mutual doubled e-pawns make things far more complicated and interesting, as we will see.

Line 1: 1...f6/1...f5

If 1...f5 (1...f6 is the same, obviously) 2.exf6 gxf6 3.g4, Black's king will run out of moves: 3...h6 4.h4 e5 (4...f5 5.g5) 5.h5 and Black loses.

Line 2: 1...g6

This move allows White to use the copycat strategy to run Black out of moves: 1...g6 2.g3 h6 3.h3 h5 (3...g5 4.g4) 4.h4 and again, Black is in a losing zugzwang.

Line 3: 1...g5

This works the same way: White copies and wins.

1...g5 2.g4 h6 3.h3 and it's over.

Line 4: The tricky 1...h6

Now things get interesting. It would seem that there isn't any difference at all between pushing the g-pawn and pushing the h-pawn: copycatting should lead to the same problem. Let's see:

1...h6 and now

(A) 2.h3 h5 3.h4 (all other moves lose, as White will rapidly fall into a fatal zugzwang, as the reader can confirm for him or herself) g5!!

Now White has three options, but amazingly, all three lose:

(A1) 4.g3 g4 and White is in a losing zugzwang position. (This was the continuation in the game, and White resigned here.)
(A2) 4.f3/4 exf3 4.gxf3 gxh4 and Black queens.
(A3) 4.hxg5 h4 and White is in a fatal zugzwang: pushing any kingside pawn leads to Black queening (5.g3 h3; 5.f3/4 exf3 6.gxf3 h3 etc.) while retreating the king loses the c-pawn and gives Black an easy win.

So 2.h3 loses!

(B) 2.g4! wins, however: if 2...g5 3.h3 is zugzwang; 2...f5/6 3.exf6 gxf6 4.h4 wins (transposing to line 1, above); finally, 2...g6 3.h4 and 3...h5 4.g5 or 3...g5 4.h5 lead to the winning zugzwang again.

By process of elimination, it's time to look at our last pawn move:

Line 5: The correct 1...h5!

Again, let's begin with a look at the copycat strategy:

(A) 2.h4? g5! and Black wins - we have transposed to the position after 3...g5 in line 4A.
(B) 2.f3/4? exf3 3.gxf3 h4! and White runs out of pawn moves first: 4.h3 f6 (or 4...f5) 5.exf6 gxf6 6.e4 (or 6.f4 f5) e5: zugzwang.
(C) 2.h3! Incredibly, only this move keeps White alive, but now things are tricky for Black again!

(C1) 2...h4 might seem best, grabbing space, but after 3.g3 Black is lost: 3...g5 4.g4, or 3...hxg3 4.fxg3 g6 (other pawn moves ensure that White gets a passed h-pawn) 5.h4 and wins.
(C2) 2...g5 3.g3 and White wins (3...g4 4.h4; 3...h4 4.g4).
(C3) 2...f5 3.h4 g6 4.g3 and once again, Black is in zugzwang and loses. This just leaves us with
(C4) 2...f6!

Now, once again, White has to be careful - all moves but one lose!

(C4a) 3.exf6 gxf6 4.f3/4 (4.h4 f5 5.g3 e5 and White is in zugzwang) exf3 5.gxf3 h4-+ and by now I'm sure the reader can fill out the details.
(C4b) 3.g3 fxe5 4.h4 g6-+
(C4c) 3.f3/4 exf3 4.gxf3 h4-+ (5.exf6 gxf6 - see C4a; 5.f4 f5; 5.e4 fxe5)
(C4d) 3.h4!

Now Black has two choices: push or capture.

(C4di) 3...f5 4.f4! (forced) exf3 (4...g6 5.g3+-) 5.gxf3 and all three pawn moves lose (as do king moves), two of them interestingly:

(C4di.1) 5...g6 6.f4 is easy.
(C4di.2) 5...g5 6.hxg5 h4 7.g6 h3 8.g7 h2 9.g8Q h1Q 10.Qc8+ Kb6 11.Qxe6+ and White wins this ending routinely.
(C4di.3) 5...f4 6.exf4 g6 looks like it puts White in zugzwang, but by sacrificing the pawn back White wins: 7.f5 gxf5 8.f4 and wins.

So, again by a process of elimination, we have the best move:

(C4dii) 3...fxe5!

Now both 4.g3 g6 and 4.f3/4 exf3 5.gxf3 e4! 6.f4 g6 win for Black, so White must try

4.g4!, when both 4...hxg4 5.h5 and 4...g6! 5.g5 look like the end of the line. It's true in both cases that Black must give up the b-pawn, but in the second variation Black has a wonderful resource:

Here Black must choose correctly, and just as in the Durham-Monokroussos ending, sometimes grabbing the opposition isn't the best way to proceed. Black's best is not 5...Kc6 when 6.Kb4 Kb6 7.c5+ Kc6 8.Kc4 Kc7 9.Kb5 Kb7 10.c6+ Kc8! 11.Kb4! Kb8 12.Kc4! Kc8 13.Kb5! (triangulation - again as in the Durham-Monokroussos ending) Kc7 14.Kc5 and White's king will have breakfast, lunch and dinner on the e-file, with two scoops for dessert if he so chooses.

The right defense is 5...Kb6! (or 5...Kd6!), when after 6.Kxb4 Kc6 White has nothing better than 7.c5. Black has one move left to find, as we've already seen that retreating will lose to triangulation, the best and only move is 7...Kd5!, when White either loses the pawn or stalemates the Black king after 8.Kxb5 - incredible!

A word on sources. First of all, it was shown to me by the famous trainer Mark Dvoretsky in a chess camp in New York in July or August of 2001, and I've since seen it published in Jacob Aagaard's Excelling in Chess Calculation - two authors whose works I can recommend for the serious chess student (for the very serious in Dvoretsky's case, and then only if you're over 2000 or incredibly dedicated). This was a very difficult ending, but Dvoretsky showed it to us (the group had an average rating of 2350-2400 or so) as a little joke, a small warm-up to the real work! But don't worry if you didn't get it; after all, the first two half-moves by the players themselves were blunders. Live and learn, and enjoy the beauty as you go along - it may not be a fully adequate motto for life, but it's not a bad attitude to carry towards the game of chess.


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