06 February 2014

Playing it Out

Sunday morning I posted "Assessing Threats," which contained a position from Exner -- Charousek 1898.

White to move

I asked whose threats are more credible? I had gone through this game and a few others to cap a week in which I had gone through every available game played by Rudolf (Rezső) Charousek. Chessgames.com has 184 games, more than any other source available to me.

It is my recollection that the star move 32.Bh4 was suggested by an engine. By creating interference on the h-file, White forces Black to deal with his threat.

In the game, White played 32.b7 and soon lost. 32...Bxh3 33.Kxh3 Rh6+ 34.Bh4 Rxh4+ 35.Kxh4 Qf6+ 36.Kh3 Qh6+ 37.Kg4 Qg6+ 38.Kh4 Qg3+ 39.Kh5 Rf5#.

It seems likely that Exner underestimated Black's attack, or thought that his was stronger.

I played out the position against Fritz 11 beginning with 32.Bh4. Along the way, I missed some nuances that maintain an advantage for White, according to Stockfish. I let y passed b-pawn fall and still had a passed c-pawn against which to contend. Even so, I was able to provoke exchanges that reduced to an opposite colored bishop ending where White easily holds. At move 82, Fritz accepted my draw offer.

Stripes -- Fritz 11
from diagram above

32.Bh4 Bd5 33.Rab1 Qc2 34.Rbf1

My move is Stockfish's third choice. The engine likes 34.Qa1 Bb7 35.Rb2 Qf5 36.Re1 Qh5 37.Be7 Rc8 (diagram)

White to move
Hypothetical Position
It is clear that Black's attack against the king is no longer a threat in this computer line, which Stockfish sees as advantageous for White. With my move, White's advantage is less.

Stockfish's second choice is 34.Qa3, which is reminiscent of the line linuxguyonfics offered in the comments to "Assessing Threats".

My battle with the engine continued: 34...Qb2

White to move

35.Rf2?

According to Stockfish, White still has a significant advantage after 35.Qd7 Bc6 36.Qc7 h6 37.Rf2. My intention was to eliminate Black's checkmate threats even at the loss of my advanced pawn. Knowing that White lost this game, I was content to play for a draw.

35...Qxb6 36.Qxb6 Rxb6 37.Be7 Rc8 38.Rd2 Bb3 39.Rd8+ Rxd8 40.Bxd8 Rb7 41.Rc1 c4

White to move

42.Ba5

I spent more than four minutes on this move, but worked out the ideas to the finish.

42...Rb5 43.Bc3 g5 44.Ra1 Bc2 45.Ra7 Kf8 46.Ra5 Rxa5 47.Bxa5 Kf7

White to move

Now, it is necessary to liquidate most of the pawns on the kingside so the king and bishop may hold all secure.

48.g3 fxg3 49.Kxg3 Ke6 50.f4 gxf4+ 51.Kxf4 Bg6

White to move

I played against the engine for another thirty moves. Occasionally. Black threatened to penetrate with the king or White threatened to win Black's h-pawn. These threats were easily parried. Once my pawn advanced to h4 and my bishop stood on the h4-d8 diagonal, while my king stood on c3, I offered the machine a draw.

1 comment:

  1. I did look at Bh4, felt that it was the move, but only analyzed it flippantly. 1.Bh4 Rh6, 2.Bg5?? Rxh3 mate. In reality, this Bh4 move serves to connect the rooks immediately, so 2.Rb1 to kick the queen is possible and the queen has no cool squares like f2 to go to because the bishop is covering it.

    This shortcoming is more indicative of my OTB chess strength. If I went "postal-chess" against an engine from a non-openings position, I would probably do quite well, as other people with high postal and lower OTB skills have done in the past.

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