Sunday; August 16th, 2009.

(Here was today's position to ponder.)

click for larger view

I thought today's problem was rather easy. Sometimes I spend many minutes puzzling over what the first move might be, in today's problem it was blatantly obvious that Black had to give up the Queen. The only real question remained as to what the follow-up might be. (I spent at least half an hour pondering the lines before looking at the game. I even printed out a copy of the diagram, and set the position up on my chess set.)

After 20...QxN/c3! 21.bxc3, I did look at the follow-up 21...exf5; but after 22.h4, considered things to be less clear.

Instead, I spent all my time looking at 20...Qxc3; 21.bxc3, Nxg5!; (my choice, and the FIRST choice of Fritz); I consider this a more forcing option.

For example, after 21...Nxg5; Black threatens ...BxP/e4+ (Kg1) and then ...Nh3#. I considered a lot of different moves, but finally decided on 22.Qe3, for White. (This move prevents Black from playing any variations with ...Nh3.) At first, I wanted to play ...BxP/e4+; but later decided that 22...NxP/e4 was best. (Threatens ...Ng3+; winning more material.) Now 23.Kg1 looks forced, when 23...RxP/c3; picks off another button. I looked at a few more moves, but my final assesssment was that Black would be winning. White's position would be in shambles, and in most variations Black emerges with a Rook, a Bishop, and 3-4 Pawns for the (lost) Queen. (In addition, Black still has a powerful initiative ... and lots of threats against White's King.)

OK, so much for the human brain, let's see what the silicon monster comes up with: [>/= 21...Nxg5!; 22.Qe3T, (22.Rfe1 Nxe4; 23.Rxe4 Bxe4+; 24.Kg1 Rxc3; 25.Qe1 Rc4 ) 22...Nxe4; 23.Kg1 Rxc3; 24.Qe1 Bf6; 25.Be3 Re8; 26.Rc1 exf5; 27.Rxf5 Ng5; 28.Bxg5 Rxe1+; 29.Rxe1 Bd4+; 30.Kf1 f6; 31.Bd2 Rxc2; 32.Re7 Bg2+; 33.Ke1 d5; " "]

conclusion: Black must give up the queen to inflict positional and material damages. Black must also take advantage of his knight, the h1-a8 diagonal to exploit the weakness of the kingside pawn and the white king

motto: Bxe4, Nxg5 and Nh3( mate or forking king and queen)

candidate: Qxc3 and Rxc3

a) 1 Qxc3 bxc3 2 Nxg5 Rae1 3 Nxe4 Rxe4 4 Bxe4+ Kg1 5 Bxf5 with great compensation for the queen

b) 1 Rxc3 Bxa5 2 Bxe4! Qg2! 3 Rxc2! ( 3 Qxc2 4 Bxc2 Rxf3 5 Be4 ) Qg3 4 Nxh2+ Kg1 5 Nxf1 Kxf1 6 Bxf5

2 Bxe4 Bxc3 3 Nxg5+ Qf3(forced otherwise Nh3#) 4 Bxf3+ Rxf3 5 Nxf3

If You look carefully, any move other than queen allows mate or losing the queen

The first thing I notice is that I have allowed my queen to be trapped. No doubt I have some ingenious reason for that, and I figure the answer has to be either 20...Qxc3 or 20...Rxc3. (In a way, this one seems not so tough. The dire situation, with White about to lose his queen, suggests a drastic response.) After a few minutes of thought, I like 20...Rxc3 better because of the continuation 20...Rxc3 21. Bxa5 Bxe4 22. h4 Nxg5+ 23. Kh2 Rh3+ 24. Kg1 Rh1#, which is not there after 20...Qxf3. If White plays 22. Bxc3 instead, then I execute the main point to the capture on c3, which is 22...Nxg5+ 23. Kg1 Nh3#

The line I see is 1. Bxc3 Nxg5+ 2. Qg2 Bxg2 3. Kxg2

<20. ... Qxc3!!>

A beautiful queen sacrifice begins a decisive attack in the long diagonal.

<21. bxc3 exf5>

Of course, <22. exf5> would be suicide: <22. ... Nxg5+ 23. Kg1 Nh3#>. And <22. Be3>, to block the defense of the knight by the rook (<22. ... Rxc3>) would be followed by <22. ... Bxe4 23. Qxf3 Rxc3> (threatening <24. ... Rxe3>) <24. Rae1 Bxf3+ 25. Rxf3 Bxg5>, and black has more pawns in the endgame.

<22. Qe2>

A little trap: <22. ... Bxe4? 23. Rxf3!>, and suddenly white wins.

<22. ... Rxc3!>

Black eludes the preceding trap and systematically increases the pressure. Now, white can't play <23. Rxf3 Rxf3 24. Qxf3 Bxe4>, and, again, black has more pawns in the endgame.

<23. Be3>

White can try not to give back his queen, but he is doomed still.

<23. ... Bxe4 24. Rxf3 Bxg5!>

The last finesse. White's bishop is pinned against the rook, which is pinned against the king. The only way to avoid the deadly <25. ... Rxe3> is to unpin the rook.

<25. Kg1 Bxf3 26. Qxf3 Bxe3+>

Black to play (20...?) "Insane"

Material: Black is up a piece, but his queen is trapped.

Candidate moves: Rxc3, Qxc3

20...Rxc3 21. Bxa5 Bxe4 22. Bxc3 Nxg5+ 23. Qg2 (not 23. Kg1?? Nh3#) exf5 24. Rxf5 Bxg2+ 25. Kxg2, and the game is far from clear. With two pawns for the exchange, Black is equal but no more.

Or even considered it.

The only thing I thought when I saw the position was, "how'd this position come about?"