Wednesday, July 31, 2013

Pawn Structures and Pawn Chains: Part 2

"Each Spartan protects the man on his left from thigh to neck with his shield. A single weak spot and the phalanx shatters"
-- Leonidas, "300"

Indeed, it is due to the uniqueness of the pawn's sideway capturing abilities that allow for such interesting phenomenon like the pawn chain! Today, I will start my discussion on how to both play with and against the pawn chain.


The diagram above represents a well-known position from the Advance variation of the French Defense. As we can see, a pawn chain is a series of pawns linked together along a diagonal, starting at the base and ending with a wedge in the central squares. Nimzowitsch wrote about pawn chains with much relish in his book "My System", and devoted an entire chapter (Chapter 9) detailing the intricacies behind it.

However, do note that the pawn chain does not appear in only the French Defence; it is also a common occurence in openings such as the King's Indian.

So let us take a look at how the chain affects the position:

  • Firstly, we can see that it divides the board into 2, creating what is known as the "two theaters of war". We will discuss about this later on.
  • Next, notice that the head at e5 is wedged within the enemy camp. This wedge gives White much space in the centre, especially on the kingside. If Black allows this wedge to remain intact, then he will have a very cramped game.
  • However, also note that if the pawns at the base of the chain get removed, the central wedge will lose its protection and will become vulnerable to attack.

Having understood all these, how will both sides proceed with their plans? For simplicity's sake, we will define the side with the pawn chain as the "attacker" and the side against the pawn chain as the "defender".


The attacker's plan: Expansion in both the centre and kingside (the two theatres of war)


From the following position, White has a small pawn chain with the head at e5 and the base at d4. The e5 pawn wedges into the enemy camp, and divide the position into two distinct battlefields: The kingside and the centre.

First, let us take a look at the kingside. The attacker's e5 pawn denies the Black knight access to the f6 square. This makes it easier for White to bring in his pieces for the attack on the king's castled position. If Black tries to gain some counterplay by attacking the pawn chain with 1... f6, then after 2. exf6 Rxf6 the e-file is now open for White to attack the weak, backward pawn on e6. This brings us to the next theater of operation: The centre

In the centre, White's e5 pawn prevents Black's e6 pawn from advancing, making it a possible target for attack. But in such a scenario, a frontal attack by the rooks are out of the question; rather, White should rely on flank advances such as f4-f5 to put pressure on the e6 pawn. If Back replies with exf5, then his d5 pawn loses protection and becomes the next target of attack.

So we can see the general strategy for the attacker: The pawn chain gives him much space in both the centre and kingside. Thus, he should desire to attack the defender in these two theaters of war.

And while he is doing this, he must be cautious to make sure his chain is well-protected, so as not to fall for countermeasures by the defender!


The defender's countermeasures: Bombardment of the enemy pawn chain base

Similar to the King's Indian, the defender's plans for play against the pawn chain will be to create an attack of his own against the chain. This said, he should not be worrying too much about the enemy chain cramping up his position; rather, he should see it as an opportunity to destroy the chain, and thus turning it from an attacking tool into a target for attack.

But careful selection of his attack must be made. For example, after 1. e4 e6 2. d4 d5 3. e5, Black can choose to attack the chain with either the c or f pawns. Now if he chooses 3... f6?, the attack will not be strong, for he is merely attacking the front of the chain, which will only destroy a part of it. Better will be 3... c5!, attacking the chain at the base.

Nimzowitsch explains this with a simple analogy "If we wished to destroy a building, we would not begin with its architectural ornaments, but we would blow up its foundations, for then the destruction of the ornaments with all the rest will follow suit."

So now after 3... c5, we can continue with 4. c3 (strenghtening the chain) Nc6 5. Nf3 Qb6 6.Bd3 (D)


We see that all of Black's previous moves were directed against the d4 square (including the Qb6, which would have seemed out of place in other positions!). Now, the best continuation will be 6... cxd4 7. cxd4, and suddenly the central chain finds itself cut off from the rest of their friends and become vulnerable to attack!

That said, it is important that after undermining the chain at its base, the defender should seek to increase the pressure on the central wedge by bringing in more pieces and pawns to attack the central squares. For example, in our earlier position, after 6... cxd4 7. cxd4 Black can bring in more pieces for the attack via moves such as 7... Ne7 followed by 8... Nf4, or a fianchetto of the king's bishop. Nimzowitsch described this repeated attack on the chain as a "slow siege of the unprotected base".


Nimzowitsch drafted the following pointers for a defender's play against the pawn chain:
  1. The enemy base, being fixed to one spot, should be attack by several pieces
  2. This pressure should be maintained as long as possible until a new weakness (e.g. another weak square) appears in the enemy camp
  3. When this happens, the defender can then leave the pawn chain along and shift his focus of attack to the new weakness. He may return to attack the weak pawn base again in the endgame
  4. The weak pawn base is often regarded as an endgame weakness, due to its vulnerability of attack by the king and rooks on adjoining open files
Most amateurs will not find Point 1 a difficult one to follow, for it has already been illustrated in my previous example. But how about Points 2 and 3? Let's take a look at the following example:

Kamenov - Galunov
Teteven 2009
Position after 11. Kf1
The position was reached after 1. e4 e6 2. d4 d5 3. e5 c5 4. c3 Nc6 5. Nf3 Qb6 6. Bd3 cxd4 7. cxd4 Bd7 8. Be2 Nge7 9. b3 Nf5 10. Bb2 Bb4+ 11. Kf1. With his last move Black has forced the White king to forgo castling. Now, he stops the siege of the pawn chain and instead transfers his attention towards the exposed position of the White king:

11... O-O 12. g3 f6 13. Kg2 fxe5 14. dxe5 Bc5 15. Qe1 Ncd4 16. Bd1 Nxf3 17. Bxf3 Nd4 18. Bd1 Nxb3 19. Bxb3 Rxf2+ 20. Kh3 Rxb2 21. Qc1 Bd4 22. Nc3 Rf2 23. Qe1 Raf8 (D)


Note how Black transfers the attack from the base of the pawn chain to White's exposed kingside. White was mated a few moves later.

See the entire game here:


...

And to summarize Part 2, here are the general plans made while playing both and against the pawn chain:

  • As the attacker, you should exploit your central space to launch attacks against either your opponent's kingside or his central pawns. As his central pawns are blockaded, they cannot be subjected to frontal attacks, but are susceptible to flanking attacks. Meanwhile, you must also make sure that your pawn chain is well supported so that it does not become vulnerable to counterattack.
  • As the defender, your best plan will be to attack the base of the enemy pawn chain with as many pieces and pawns which you can throw at it. This siege can be maintained until a new weakness is opened up in the enemy camp, upon which you should seize the opportunity and transfer your forces from the pawn chain to the new weak point. Also, do bear in mind that in the endgame, an unprotected pawn base is usually a weakness.

So far, we have been looking at what are the plans for both sides while the chain is still intact. In Part 3, we will investigate what happens during the stage when the chain starts to fall apart-- how the defender can exploit this change in events, and how the attacker can salvage the position.

Links:
Part 1: http://nushsblackknights.blogspot.com/2013/07/pawn-structures-and-pawn-chains-part-1.html


Sources:
http://lotr.wikia.com/wiki/Battle_of_the_Hornburg
"Understanding Pawn Play in chess" by Drazen Marovic
"My System, 21st Century Edition" by Aaron NImzowitsch
"Pawn structure chess" by Andrew Soltis

Tuesday, July 30, 2013

The skewer

Alright guys, more tactical presents for y'all:

Let's begin with a warm-up! White to move

Now that your engine is running...Black to move

One small step for man, one giant leap for White

Black to move. Exploit the pin to create a skewer

Looks drawish...or is it? White to move


We'll finish off with Black to move

Sunday, July 28, 2013

Pawn structures and pawn chains: Part 1

I'm not sure how many of you have heard of this quote by André Philidor: "Pawns are the soul of chess". And of course many people will think: This Frenchman from the 18th century is telling me not to worry about my rooks, my queen, not even the safety of my own king. He's telling me to worry about my pawns!?

Pawns are often looked down upon by many amateurs as they have limited movement, and often get into the way of the mighty pieces. Yet it is the limited mobility of the pawn which makes it such an important feature in gameplay. More often than not, a pawn structure will be established in the opening, and usually remains unchanged throughout the game. Because of this, the pawn structure is often regarded as the skeleton of the game.

And with that, I introduce the topic on pawn structures and pawn chains.


To paraphrase from Andrew Soltis in his book "Pawn Structure Chess" (1995), the pawn structure is what forms the terrain of the battlefield. The pawn centre offers the high ground that every commander desires, while open files and diagonals represent the valleys and ridges that give the attackers access into the enemy camp.

Not surprisingly, a thorough knowledge of the terrain will be very helpful in securing the roads to a victory. History has proven to us time and again this fact:

1939 Winter War: The Finns knew the terrain better than the Soviets, and look at what happened. Photo courtesy of: www.wikipedia.org
So how exactly do we exploit the nature of a pawn structure? Let's look at an example, taken from a typical Sicilian Dragon position:

Position after Black's 10th move
At first glance, the features of the pawn structure does not seem very obvious to us. So to make things easier, let us first strip the board of all pieces (including kings!) and look only at the pawns:


And now, everything about the structure suddenly seems so obvious to us! The prominent features of this terrain will be the semi-open c and d files, the open a1-h8 diagonal, and White's centralized pawns. Let's go through each of them one by one.
  • We can clearly see that White enjoys more space in the centre. Placing a rook along the semi-open d-file will also help him in preparations for a centre breakthrough
  • The Black pawn structure, on the other hand, offers a semi-open c file as well as the long a1-h8 diagonal. Should we now magically drop a Black rook on c8 and a Black bishop on g7, we can see that both pieces are aiming at the queenside, ready for an attack
  • But the hole on g7 also represents another feature of the game. Notice that with no bishop occupying it, the dark squares around Black's kingside become very weak, and this offers chances for White should he decide to launch an attack on the kingside.
So now, let's place a few more pieces on the board to verify our analysis:


From the position, it is obvious that Black's rook and bishop will be able to attack the queenside when the c-file and a1-h8 diagonal are clear of other pieces. White will also have to deal with the weaknesses of his pieces on the queenside, namely the exposed position of his king as well as his hanging light-squared bishop

However, the weaknesses of the dark-squares on Black's kingside will become obvious should he end up losing his dark-squared bishop. Also, notice that White's bishop and rooks are poised to strike towards both the centre and kingside. These features allow White to prepare for a kingside attack.

Finally, when we look back at the original position:


We can now formulate the basic plans for both sides. For Black, he will try to exploit his occupation of the semi-open c-file and the a1-h8 diagonal to launch an attack on the queenside. He will try to do this by doubling-- or tripling-- his major pieces along the c-file, clearing the a1-h8 diagonal for his fianchettoed g7 bishop, and shifting the rest of his minor pieces over to aid in the attack. While doing this, he must be careful not to mindlessly trade off the g7 bishop lest he open up weakness in his kingside dark squares.

On the other hand, White will first try to resolve his queenside weaknesses before seeking counterplay on the kingside. He will do this by launching a pawn storm with his f, g and h pawns, and shift both major and minor pieces over to that wing to support the attack. In most games, White uses a pawn sacrifice to open up the h or g file before bringing in his major pieces.

And thus, this is a good example of how the structure of the pawns decides the nature of the game to come.

...

Want another example? Let's take a look at a position featuring a kingside Stonewall:

Capablanca, Jose Raul vs Illa, Rolando
Buenos Aires Casual 1911
Position after Black's 6th move
Once again, we will take away the pieces first and look only at the pawns:


What strikes us now are the relative strengths and weaknesses among the central squares. White's d and f pawns exert strong control over the e5 square, and the f4 pawn also threatens to push further should White decide to attack kingside. The e5 square is a potential outpost for White's knight, from which it can exert great pressure within the enemy camp.

A great weakness for White's pawn structure will be the hole on e4. Similarly to White's plan on e5, Black can also utilize the e4 square as an outpost for his knight.

Also, note that should both sides decide to exchange pawns on d4, the c-file will be opened up and has potential use by both sides.

Now, let us put the minor pieces onto the board:


As we look at the board, here's a quick question: In such a position, are the bishops or the knights stronger?
.
.
.
.
.
.
.
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If you answered that the knights are stronger, then you're right! The position above is still closed, and features no open diagonals for the bishops to exploit (although this may very well change should exchanges occur on the central squares). In fact, White's dark-squared bishop and Black's light-squared bishop are considered bad bishops as they are being blocked by their own pawns

On the other hand, we can now see the White's knights can maneuver to the e5 outpost via Nf3-Ne4 with ease, while the same goes for Black and his e5 outpost. Note that from e5, the White knight can exert control over most of the squares on the kingside, disrupting enemy operations and paving the way for an attack of his own on that wing.

And now, looking back at the original position, the plan for White will be clear: He will try to trade off his bad light-squared bishop to improve his position, and move his knight to the outpost on e5. From there, he can then exploit his outpost and his advanced f5 pawn to launch a kingside attack.

Black, on the other hand, has a number of plans at his disposal. He can try to dampen White's attack by trading off White's dangerous light-squared bishop, open up the central position to weaken White's knights, or open up the c-file to seek counterplay on the Queenside.

See the entire game here:


...

As such, I hope that y'all have learnt to better appreciate the importance of pawn structures in a game, and how to exploit its various features to create a better position for yourself. In Part 2, we will investigate a unique but well-known pawn structure: The pawn chain.

The pawn chain

Sources:
"Pawn Structure Chess" by Andrew Soltis

Friday, July 26, 2013

Another passed pawn: Whampoa Rapids 2013

Opponent vs Checkerboard 5
Whampoa Rapids 2013


1. e4 c6
2. Nf3 d5

I always love it when my opponents advance that pawn. It closes up the centre, blocks that annoying Bb5+ and allows me to prepare the flanking move c5.

3. e5 Bf5
4. d3?! e6
5. Nd4 Bg6
6. Nc3 Bc5
7. Be3 Bb6

Now I felt that 7... Nd7 would have been better, developing a piece in the process

8. Qe2 Ne7
9. O-O-O O-O (D)


10. g3??

My opponent, in his haste to free his light-squared bishop, fell into a tactical trap. The most direct continuation would have been 10. h4 c5 11. Ndb5 d4 12. h5! Bf5 13. g4!, and now if Black tries to grab a pawn with Bxg4?! the game will continue 14. Qxg4 dxe3 15. h6! with attacking chances for White in compensation for his lost pawn.

But now after the text move, White's game quickly crumbled after a tactical blow:

10... c5!
11. Nb3 d4
12. Nb5 dxe3
13. Bg2 Nbc6
14. Bxc6? Nxc6

Exchanging pieces will only be in my favour

15. d4 cxd4
16. fxe3 Qg5
17. Kb1 dxe3

And the passed pawn materializes. While it currently cannot advance, it ties down the White Queen to the blockade-- quite embarrassing for a royal piece to find herself guarding a foot soldier!

18. Rd7 Nb4
19. Rc1 Rac8
20. Na1 (D)


With the constant threats on the c2 square, White is reduced to passive defense.

20... Rfd8
21. Rxd8+ Rxd8
22. a3 Rd2
23. Qc4 h6
24. axb4 e2!
25. Re1 Rd1+
0-1

Position after 25...Rd1+
The far-advanced passed pawn, coupled with the rook's entry into the 7th and 8th ranks, proved decisive.

Once again, all comments/alternative viewpoints are welcome!

Wednesday, July 24, 2013

Hypermodernism and the King's Indian: Part 5

Today, I will end off my series on the King's Indian with a game illustrating what happens if Black does not defend properly. In this instructive game, White was able to utilise his pawn centre to give him a powerful passed pawn that eventually won the game for him.

Botvinnik, Mikhail vs Tal, Mihail
World Chess Championship 1961 (Round 13)


1. d4 Nf6
2. c4 g6
3. Nc3 Bg7
4. e4 d6
5. f3 (D)


Botvinnik plays the Samisch variation.

5... O-O
6. Be3 e5
7. dxe5 dxe5
8. Qxd8 Rxd8
9. Nd5 Nxd5
10. cxd5 (D)


Over here we have an interesting position. The series of exchanges has left White with a pawn chain headed by the d4 pawn. This serves to close up the centre, and the d4 pawn drives a wedge deep into the Black camp.

Now, Tal seizes the opportunity to begin a queenside expansion.

10... c6
11. Bc4 b5
12. Bb3 Bb7
13. O-O-O c5?

A slight inaccuracy in Black's plan: While he continues to expand on the Queenside, he also helps to create a strong, protected passed pawn for White! A more accurate possibility would have been 13... a5, threatening 14... a4 and at the same time keeping the d4 pawn under control. Now if Black attempts 14. d6?! the game can continue 14... Bf8 15. Bc5 Na6! and Black wins a pawn.

14. Bc2 Nd7
15. Ne2 Bf8
16. Nc3 a6

Now, White's plan will be to first nullify any attack carried out by Black on the queenside, before lauching his own attack to open the queenside files for his rooks. This will help to bring his rooks into the enemy camp, where, coupled with the passed d4 pawn, will secure a decisive advantage for him.

17. b3! Rac8
18. Bd3! Nb6
19. Be2 Rd6
20. Kb2 (D)


White successfully blocks out any possibilities of a queenside expansion. What seemed like an aggressive assault by Black earlier is now an immobile mass of pawns with the pieces stuck behind it. With his plans disrupted, Black has no choice but to seek counterplay on the kingside:

20... f5
21. Rc1 Rf6
22. a4!

Having defended against Black's attack, White now proceeds with his own blow, which breaches the black rampart and opens the files for his rooks

22... bxa4
23. bxa4 a5
24. Kc2 c4
25. Rb1 Bb4
26. Na2 Bc5
27. Bxc5 Rxc5
28. Nc3 Bc8
29. Rb2 Bd7
30. Rhb1 Bxa4+
31. Nxa4 Nxa4
32. Rb8+ (D)


And White breaks through the queenside after securing full control of the b-file

32... Kg7
33. R1b7+ Rf7
34. d6

The moment has arrived! With most of the pieces exchanged off the board, Black has insufficient material to set up a successful blockade of the passed pawn. The advance of this mighty pawn, coupled with the rooks on the 7th and 8th ranks, prove to be decisive.

34... Rxb7
35. Rxb7+ Kf6
36. Rxh7 Rc8
37. d7 Rd8
38. Bxc4 Nc5
39. Rf7+ Kg5
40. Bb5 fxe4
41. fxe4 (D)
1-0

Final position after 41. fxe4

Black's failure to undermine his opponent's pawn centre enabled White to create a powerful passed pawn, which lay low until the enemy's blockading pieces were off the board. This shows how inaccurate play by Black in the King's Indian can lead to serious repercussions.

And with that, I close my series of articles regarding hypermodernism and the King's Indian. Next time, I will talk about pawn structures and pawn chains.

Links:
Part 1: http://nushsblackknights.blogspot.com/2013/07/hypermordernism-and-kings-indian-part-1.html
Part 2: http://nushsblackknights.blogspot.com/2013/07/hypermodernism-and-kings-indian-part-2.html
Part 3: http://nushsblackknights.blogspot.com/2013/07/hypermodernism-and-kings-indian-part-3.html
Part 4: http://nushsblackknights.blogspot.com/2013/07/hypermodernism-and-kings-indian-part-4.html

Saturday, July 20, 2013

Hypermodernism and the King's Indian: Part 4

It's been a while, my fellow Black Knights. Let us continue where we left off last week: Strategies of the King's Indian

Sometimes, a direct attack against the centre doesn't always guarantee Black a victory. Very often, the centre can become closed, and it can become difficult for Black to launch attacks against White's pawn centre.

In such situations, a good plan for Black will be to launch a kingside attack, especially since by then he will have already played the f5 pawn break (which opens up the kingside for his pieces). White, on the other hand, will look for counterplay on the queenside, where his far-advanced d pawn can offer chances of supporting the attack.

In some games these plans can result in a race for both sides to attack each other on their respective wings, as we will see in the following game:

Korchnoi, Viktor vs Kasparov, Garry
Amsterdam 1991


1. Nf3 Nf6
2. c4 g6
3. Nc3 Bg7
4. e4 d6
5. d4 O-O
6. Be2 e5
7. O-O Nc6
8. d5 Ne7
9. Ne1 Nd7
10. Be3 f5 (D)


And now we have a typical King's Indian position with a flank attack on f5

11. f3 f4
12. Bf2 g5

The centre is closed, and now Black wants to attack the kingside...

13. a4

...while White seeks play on the queenside.

13... Ng6
14. Nd3 Nf6
15. c5 h5 (D)


16. h3? (D)

An inaccuracy in White's plan. Most of you should know that in a position where both sides are carrying out attacks on opposite wings, it is usually not advisable to push pawns on your weaker wing-- it usually wastes valuable tempo required to carry out your attack. And in such double-edged positions where both sides are racing to attack the other, tempo is VERY important!

While 16. h3 seems like a forced defense to prevent 16... g4, many commentators pointed out that it was possible to continue on with the game via 16. cxd6 cxd6 17. Rc1 g4! 18. Nb5! g3 19. hxg3 fxg3 20. Bxg3, where White stands in a good stead.

To divert a little from the main game, I want to take a look a related game (Schmidt - Galonska, Recklinghausen 1995) where a slightly similar position was reached after the 15th move:


After 1.Nf3 Nf6 2.c4 g6 3.Nc3 Bg7 4.e4 d6 5.d4 O-O 6.Be2 e5 7.O-O Nc6 8.d5 Ne7 9.Ne1 Ne8 10.Be3 f5 11.f3 f4 12.Bf2 h5 13.c5 g5 14.a4 Ng6 15.a5 Nf6 (D)


And now, instead of trying to defend with 16... h3, White ignores his opponent's threats altogether and proceeds with his own attack:

16.cxd6 cxd6 17.Nb5 g4 18.Bxa7 g3 19.Bb6 Qe7 20.Kh1 Kh8 21.Nc7 Rb8 22.Rc1 Rg8 23.Ne6 Nf8 24.Rc7 Bd7 25.Bb5 Bh6 26.Qc2 Ng4 27.fxg4 hxg4 28.Nxf8 Rbxf8 29.Bxd7 Qh4 30.h3 f3 31.Bxg4 Rxg4 32.Nxf3 (D)


Black's attack has been fended off, while White has managed to break through the queenside. Black eventually resigned on the 41st move

...

Returning to the Korchnoi - Kasparov game, you can see how one small loss in tempo can very well decide the game! Now, Black gets a breath of valuable time that allows him to surge ahead with his attack:

16... Rf7
17. c6 a5
18. cxb7 Bxb7
19. b4 Bc8
20. bxa5 Bh6
21. Nb4 g4
22. Nc6 Qf8
23. fxg4?

Opening up the h-file and allowing Black to break through. Perhaps 23. h4 could have helped to dampen the attack a little

23... hxg4
24. hxg4 Bg5
25. Bf3 Qh6 (D)


It should be quite clear by now that Black is starting to win the race, despite his two-pawn deficit

26. Re1 Nh4
27. Bxh4 Bxh4
28. g5 Qxg5
29. Re2 Ng4
30. Rb1 Bg3!
31. Qd3 Qh4 (D)
0-1

Final position after 31...Qh4
With the threat of 32.... Ne3, followed by 33... Qh2+ and 34... Qh1+, Black saw no point in playing any further

This is a very instructive game featuring the King's Indian, and it also demonstrates the importance of tempo in such attacking positions. Korchnoi defended well, but his inaccuracies proved to have a greater effect than he could have imagined. I recommend that you look through it a few more times to grasp the concepts behind it.

...

So what happens if Black fails to defend properly in the King's Indian? In Part 5, we will take a look at a game where White manages to crush Black with a well-supported pawn centre.

Links:
Part 1: http://nushsblackknights.blogspot.com/2013/07/hypermordernism-and-kings-indian-part-1.html
Part 2: http://nushsblackknights.blogspot.com/2013/07/hypermodernism-and-kings-indian-part-2.html
Part 3: http://nushsblackknights.blogspot.com/2013/07/hypermodernism-and-kings-indian-part-3.html