An unexamined life is not worth living.

Monday, February 28, 2011

Solving Susan Polgar’s puzzle

Solving this chess puzzle from Susan Polgar’s blog, I had a bit of a dilemma, choosing between transforming the position into one of two possible endgames.
Kulon – Juracz, 2011
image Black to move.
Everyone answering the question (other than me) – decided on the exchange sacrifice 1… Rxa2 2. Rxa2 Bb2.

OPTION 1 – “Pawn endgame”
image  White to move. I quickly considered this position, which is practically equivalent to a pawn endgame, and it appeared slightly unclear. However because Black bishop covers ‘d4’ and ‘e5’, White will loose the d5 pawn and the game because of zugzwang. Everyone else who answered the puzzle in comments on the blog – went for this solution. I however chose a more complicated way, which I think is also sufficient for a win.

Why not just trade rooks with 1… Rxe2 2. Kxe2 f5 and go for endgame with bishops of opposite colour – which I am a big fan of:
OPTION 2 – Bishop Endgame
image White to move. Two passed pawns are hard to stop in the long run – in quick analysis I was unable to hold this for White. Black king threatens to break through to b2, so White has to guard against that, but otherwise Black forms a passed pawn on the kingside. For example: 3. Kd3 Kf8 4. Kc4 Ke7 5. Kc5 Bd6+ 6. Kc6 g5
image Black pawns begin marching 7. Kb5 Kf6 8. Kc4 Ke5 9. Kc3 h5 10. Bb1 g4 11. hxg4 fxg4 12. Kd2 Kf4 13. Ke1 Kg3 14. Kf1 Kh2 15. Kf2 h4 16. Kf1 g3 17. Ba2
image Black to move. 17…h3  wins on a spot.

If White chooses a different plan, and transfers the king to guard the ‘a’ pawn and free up the bishop, we can get a position like this:

image Black to move. 1…f3!? 2. fxg4 g3!? creates an instructive position:

image Black wins because his bishop guards both of White’s pawns from the same diagonal – as per Mark Dvoretsky’s teachings.

Success in chess depends on knowing typical ideas and recognizing those patterns on the board. Sometimes there is more than one way to win the chess game – in a tournament you only need to find one! In analysis, we can, however, muse around and come up with multiple solutions for our own entertainment…

No comments:

Post a Comment

Hit Counter