Sunday, April 21, 2013

Positional Analysis II - A Knight's Tale

I recently blogged about a methodical way to analyse positions and formulate plans:

Breaking down a position into these 7 criteria and analyzing them in turn is a very useful technique to evaluate a position and formulate plans:

1. Material Balance
2. Immediate Threats
3. King Safety
4. Open Files
5. Pawn Structure, Strong and Weak Squares
6. Center and Space
7. Development and Coordination among minor and major pieces

Using this approach, we recently looked at another game. The following position is from the 13th game of the 1978 World Championship match between Victor Korchnoi and Anatoly Karpov.
Korchnoi - Karpov, Game 13, World Championship 1978, Baguio
1. Material Balance: The material balance is even. White has a light-squared bishop, Black a dark-squared one.
2. Immediate Threats: Immediate tactical threats do not exist.
3. King Safety: The position of both kings has been compromised to some extend. Both Black and White have advanced their kingside pawns a little bit, resulting in weaknesses for both players. However, as both players castled kingside, neither player can be too reckless about attacking the opponent without exposing their own king, too. Considering the situation on the queenside, king safety is probably not a key factor in this position.
4. Open Files: There are currently no open files. Black can take control of the semi-open e-file. White's pawn on e3, however, is well protected and due to the support from the pawn on f2 not a good target for Black. White on the other hand controls the semi-open c-file and can easily put a lot of pressure on Black's c6-pawn. 
5. Pawn Structure, Strong and Weak Squares: White has weak squares on a4, c4, h4, and to some extend e4 (because playing f2-f3 makes the e3-pawn a much easier target), Black has weak squares on a6, e5 and f6. 
6. Center and Space: It's a half-open center. Both sides have a lever to potentially open it at some point. White could play e3-e4 to attack Black's pawn formation in the center. However, for the time being this is not recommended because after Black takes on e4, his battery on the d-file would immediately exert tremendous pressure on White's d4-pawn. Black on the other hand could conceivably play c6-c5 sooner or later but only White gives up control over the c5 square.
7. Development and Coordination among minor and major pieces: Both sides are fully developed. White has a considerable space advantage, especially on the queen side and is much better able to regroup his pieces. Black's major pieces seem oddly misplaced on the d-file, which won't open any time soon. Both players also need to find better squares for their Knights.

Conclusion: White has the much easier game. He has more space, and a simple and straightforward plan: put pressure on Black's weak c6-pawn. It seems that Black can't do much other than defend the weakness on c6. 

Standard chess strategy describes several ways how Black can defend a weakness like the pawn on c6:

A) Black can try to defend the pawn and protect it with as many pieces as possible. This is typically the worst and most passive option and only recommended in situations when options B) and C) are unavailable.
B) Black can try to get rid of the weakness by playing c6-c5 to exchange the pawn. That of course is usually a very effective way of dealing with weaknesses. However, this approach won't work here because White controls the c5-square and won't allow Black the freeing maneuver c6-c5.
C) Black can try to generate counter play elsewhere on the board to distract White from attacking the c6-pawn. This does not work here either because Black can not open the center, and does not have a way to create promising counter play on the kingside.

However, Karpov found an astonishing move. He played Pawn b6-b5!
Pawn b6-b5 is the beginning of a remarkable repositioning of the Knight on c7
Pawn b6-b5 is a truly remarkable solution to Black's problems. The move is highly anti-positional and would under normal circumstances be just terrible because it only aggravates Black's problems on the queenside:
1. After b6-b5, Black no longer has the potential lever c6-c5. The move takes away most of Black's queenside pawn mobility
2. The move also surrenders the critical c5-square to White, and gives up control over a5

Of course, Karpov was aware of all this. He played Pawn b6-b5 anyway because he realized that this move also creates a formidable outpost for his Knight on c4. On c4 the Knight blocks the c-file and completely paralyzes White's queenside play. The weak pawn on c6 no longer needs to be defended, and Black can put his pieces to more active use.

After a few more moves, the players reached the following position:
In just a few moves Black has completely swung momentum in his favor
Through one brilliant maneuver Black managed to swing momentum almost completely in his favor. Black still needs to do something about his misplaced Rook on d6, but the weakness on c6 is securely defended thanks to the Knight on c4, and suddenly it looks like White's b4-pawn might be in a bit of trouble. It's probably premature to say that Black has an advantage in this position, but he has definitely fully equalized. 

Black eventually won the game.

Why I chose this example:
1. I still remember how eye-opening I found this position when we analyzed it at my chess club many years ago. I realized that I would have never found a maneuver like Kc7-a8-b6-c5 on my own. In fact, in my games at the time I wasn't even looking for such maneuvers. Thanks to this game and a few similar examples the coach showed us at the time I was able to expand my arsenal of strategic ideas. Today, I wouldn't miss an idea like this in a serious game.
2. I like this position because it is a little more difficult to analyze than the previous example from the Gelfand-Ivanchuk game from the 2013 London Candidates Tournament (link at the beginning of this article). In that game, White's very bad bishop makes it pretty easy for Black to formulate a plan. In this example, all Black really has is a weakness on c6. Coming up with the right idea is much harder. 

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