Keeping Momentum in the Attack - Opposite Side Castle Sicilian

Keeping Momentum in the Attack - Opposite Side Castle Sicilian

FangBo
FangBo
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Welcome!

Inspired by Kotov's classic 'Think Like a Grandmaster', a book all about the art of analysis and calculation, I have decided to look more deeply into one of my own games, which reached a critical climax containing many different attacking strategems, and one where I also failed to find the correct sequence of moves, to orchestrate the attack.

It may be interesting to note how the position arose - It was a Sicilian with opposite side castling, renowned for leading to sharp doubled-edged positions. I was the first to get the attack in, however my opponent was not allowing any simple win. 

Critical Middlegame Position

Here, it is crucial that black finds the right strategy, otherwise white will trade off into a favourable ending a pawn up. There is no time to lose, because white has the threat of Bc1 - b2, when black's attacking potential has effectively evaporated.

What plans for black, and how to achieve them?

Here are some of my thought processes I had, as I looked for candidate moves:

  • If I could put a rook on a1 it would be checkmate. How about Ra8 and axb3 (or axb3 first)? In that case, does the rook sacrifice on a2 work? e.g. 26... axb3 27. cxb3 Ra8 (now some pointless move) 28. h4 Rxa2 29. Kxa2 Qa7+ 30. Kb1 Qa1+ 31. Kc2 Qb2+ 32. Kd3 and the king is running to the other side of the board!
  • Can I blast open the formation with sacrifices on b3? e.g. 26...axb3 27. Bxb3 Qxb3 28. cxb3 No there are too many defenders of b3.
  • Can the queen invade on the dark squares? - e.g. 26...Qc5 27. Qe2 (27. Bc1?? Qxc4!!) …Qa3 28. Bc1 Just in the nick of time! How about preceding the whole sequence with axb3, to open up the a-file. e.g. 26...axb3 27. cxb3 Qc5 28. Qe2 Now neither 28...Ra8 works (due to Bc1 - revealing the g2 rook) nor does 28...Qa3 due to 29. Bc1 and if 29...Qxa2+ 30. Rxa2, or even 30. Kxa2, because the c2 square is free for the king's escape.

I looked at the clock, and I had wasted 25 minutes without finding any decent way to continue the attack. So I just played 26...axb3?! and after a further mistake drifted into a losing ending, but what I am interested in, is how black could have continued the attack. The thought that I did not have was:

"My light squared bishop is a bad piece, is there any way to get it involved"

It is now clear to me that the strategy needs to be based around developing this piece somehow.

Here are my candidate moves:

  1. f5 
  2. f6
  3. Be8
  4. g6
  5. Qc5

Let's consider each in turn:

A) 26...f5

A1) 27. gxf5? Bxf5 28. Qe2 axb3! 29. axb3... Winning for Black.

A2) 27. Qe2 (27. Qd3 is pretty much the same thing) fxg4 28. fxg4 Qc5 Winning for Black.

B) 26...f6 A slower idea. 27. Bd3 threatens checkmate 

B1) 27...g6 28. b4! closing down the b-file 28...f5 29. Qe2 e4 30. fxe4 fxg4 and black's attack has fizzled out.

B2) 27...f5?! In principle, this move seems like a waste of time. 28. Qe2 fxg4 29. fxg4 Compared to the 26...f5 line this one wastes a move, which allows the white light squared bishop to get to d3 with tempo. Therefore we can rule out f6 for black.

C) 26...Be8 Trying to reach the h7-b1 diagonal, so that it can pin c2. 27. Bd3 threatens checkmate again.  27... f5 (27...g6 goes against the principle of Be8) 28. gxf5 and the bishop on e8 has failed to achieve its mission. So we can rule out Be8.

D) 26...g6 Preparing f5, here White has a few options:

It seems that g6 has little value in itself, and is only a half-decent move because you can use the ideas shown in the A variation, by playing Rfc8.

E) 26...Qc5 This move has more than one idea behind it. Firstly to start an attack on the dark squares, and secondly to take the bishop on c4, by using the pin. It is a key move to the position, as we can see by some brief calculation... 

E1) 27. Bc1?? Qxc4 wins a piece and the game. Winning for Black.

E2) 27. Qd3 Probably what my opponent would have played. 27...Rfc8 renewing the threat of Qxc4. 28. Ba6 Rc7 White is in some kind of zugzwang. Winning for Black.

In conclusion, both 26...f5 and 26....Qc5 are winning moves for black, provided that they are followed up with the correct strategy. The move I played in the game releases the tension prematurely, and allows white to gather his defences together.