Friday, December 30, 2016

Kickoff 2017 Tactical Challenge

Giving them out early because I will be on duty during the New Year.






Have fun, and Happy New Year to all!

Thursday, December 29, 2016

A story of doubled pawns: Part 4

As promised, we will be looking at instances of doubled pawns affecting the endgame. Now we know that due to their slow mobility and inability to protect each other, they are not very effective in offensive operations. Such is also true in the endgame. Take for example the famous rook-pawn endgame:

Position 1: A drawn rook-pawn endgame

Anyone with basic endgame knowledge knows this is a draw so long as Black gets his king to the promotion square. But if we added another White pawn anywhere along the a to g-files, then the presence of two passed pawns spells doom for the Black king.

What if we placed that extra pawn on the h-file, creating doubled pawns? Then the additional material makes no difference, because the rear pawn cannot provide any support. Neither can he hope to become a queen himself because his front comrade is blocking the way.

"Coming in one at a time ain't gonna help ya, mate"

It is however interesting to note that for non-rook pawns, the extra pawn does make a difference even if in the form of doubled pawns!

...

Another case of unsuccessful offensive campaigns involving doubled pawns would be the opposite-colour bishops endgame:

Position 2: A drawn opposite-colour bishops endgame

This is another basic draw. Even though Black's king is in the middle of nowhere, he just needs to keep his bishop on the long diagonal, prepared to be sacrificed should the enemy pawn advance.

If we add an extra pawn behind the existing one, White wins since he can advance his pawn and exchange it for Black's bishop. He will still have another pawn left to promote.

But if Black now gets his king involved in the action, then both king and bishop can work to stop the pawns, and the presence of extra pawns behind won't make a difference:

Position 3: Doubled pawns won't help if Black's king is near

This is where the weakness of doubled pawns stand out. Once again, the rear pawn can't do anything to help the advance, since both enemy pieces guard the forward square. It doesn't matter if there are 3, 4 or even 5 pawns waiting in line!

Nope, White isn't going anywhere

...

One more example we will look at is the Philidor Position. From two earlier articles here and here we know this is another draw for the defender, regardless of which side to move.

Position 5: Another draw

Are the results any different if White had another pawn on d4? No, Black can still draw, but he needs to be a little more careful. The extra pawn means the White king has more chances to seek shelter from the rook checks!


Can doubled pawns be good in an endgame?

Having seen so many endgames where having doubled pawns is as good as having only one pawn, one naturally wonders if the opposite can be true. Can doubled pawns actually benefit a player in the endgame?

In all the examples we saw so far, the side with doubled pawns is hampered when using them in the offensive. But these unique foot-soldiers, while weak in the attack, turn out to be very useful in defensive operations.


Position 6: White's pawn majority proves decisive


In Position 6, Black's passed pawn is rendered useless, and White will simply advance his pawn majority on the other wing to create a passed pawn and an effortless win.

Enter doubled pawns, and suddenly White cannot advance his pawns without giving Black a passer of his own!

One real life example of this occured in the game Eliskases - Bogolijubov 1939, where Black was a pawn up in the endgame, but couldn't create a passed pawn due to the power of White's doubled pawns:


Wrapping up

From what we learned so far, it can be concluded that doubled pawns are generally bad for attacking but very valuable in defense (with important exceptions, of course). This is also true in the endgame, judging by our earlier examples.

In Part 5 and the final article in this series, we will wrap up with a few miscellaneous but interesting games involving the doubled pawns.

Links:
Part 1: http://nushsblackknights.blogspot.com/2016/11/a-story-of-doubled-pawns-part-1.html
Part 2: http://nushsblackknights.blogspot.com/2016/11/a-story-of-doubled-pawns-part-2.html
Part 3: http://nushsblackknights.blogspot.com/2016/12/a-story-of-doubled-pawns-part-3.html
Part 4: http://nushsblackknights.blogspot.com/2016/12/a-story-of-doubled-pawns-part-4.html
Part 5: http://nushsblackknights.blogspot.com/2017/01/a-story-of-doubled-pawns-part-5.html
Sources:
"Silman's Complete Endgame Course" by Jeremy Silman
https://www.chess.com/article/view/the-truth-about-doubled-pawns-part-3
https://en.wikipedia.org/wiki/Battle_of_Stirling_Bridge

Saturday, December 24, 2016

Christmas Tactical Challenge 2016

I'm getting really predictable. Who can miss an important date without some good puzzles?





Have fun, and Merry Christmas!


Sources:
http://www.today.com/home/5-tips-keep-your-christmas-tree-alive-through-holidays-t58821

Saturday, December 17, 2016

World Chess Championship 2016 Highlights: Part 2

Today we will continue on our analysis of selected WCC 2016 games. While in Part 1 we saw a simple victory by Carlsen in the rapid tiebreakers, this time we will look at the multiple times he tried to break down Karjakin in the classical games - and failed. Rounds 3 and 4 of the match were hailed as miracle escapes by Karjakin, as well as a showcase of his unwavering defensive skills.

Maybe if you fire enough rounds, one will hit him

In both games, we will see how close Carlsen got to demolishing his opponent, yet Karjakin stood his ground and managed to split the points after more than 7 hours of play.

A close shave for the Russian GM!


Carlsen vs Karjakin, WCC 2016 Round 3

As both rounds played well into the endgame, naturally there will be groans of despair should one try to click through every individual move. To make things more interesting, I have taken a leaf out of GM Daniel King's video, and divided the endgame of Round 3 into several key positions:

Game 1, Position 1 after 22... Kf6

Position 1. Both sides have simplified into a rook + bishop vs rook + knight ending. Although having pawns on both sides of the board usually favour the bishop, here there are so many pawns the position is rather cramped, thus the knight has a slight edge.

Carlsen, as White, continued 23. Nc4 followed by 24. Re8, taking control of the e-file and gaining better placement for his pieces. Karjakin on the other hand attempted to open up the position to help his bishop.

Game 1, Position 2 after 31. b3

Position 2. Although White had the initiative from the earlier position, Black has managed to generate some counterplay with his rook on the enemy's 2nd rank. His pawns are also ideally located on light-squares, giving his dark-squared bishop free reign.

One suggested continuation here is 31... d5, fixing White's queenside. Although Black drops a pawn after 32. Rg5, he can get sufficient counterplay against the queenside weaknesses with 32... Ke6 33. Rxg5 Bg7!

Instead, Black in his haste to further open the position for his bishop, played 31... c5? weakening his pawn structure and handing the advantage to White.

Game 1, Position 3 after 61. Kf3

Position 3. White already has the edge here thanks to his extra passed pawn, although Black has a blockade on it. However, after further mistakes by Black, White managed to infiltrate his opponent's kingside via the light squares, pushing him back with king and both pieces and gaining a huge advantage.

Game 1, Position 4 after 70... Kxf5

In our final position, we see that Karjakin has given up his remaining minor piece to prolong the struggle. Naturally most of us would think that it should be an easy win for Carlsen, but there is a catch: If Black can win the b3 pawn, the resulting rook + knight vs rook endgame is a draw.

In his attempts to hold onto b3, Carlsen slipped and gave Karjakin valuable time to generate counterplay with his h4 pawn. The game was eventually drawn on move 78.

Enough talking, let us play out the endgame with the 4 positions described:


What can we learn from this game?

  1. Sometimes, it is alright to damage your pawn structure to gain better piece activity... but sometimes it's not. You need to have sound analysis of the position before making such a decision
  2. When defending a rook endgame, avoid trading off the rooks, and keep your rook active by finding targets in the opponent's camp
  3. Similarly, when down on material, trade pawns instead of pieces, so that your opponent does not get easy king-pawn endgames


Karjakin vs Carlsen, WCC 2016 Round 4

For those who have been following my doubled pawns series, this game will already be familiar to you: Carlsen obtained a huge advantage by taking control of the light-squares and b-file, despite having doubeld pawns. So how did Karjakin defend? Today we will look at the endgame, where similar to Game 3 Carlsen missed an opportunity and allowed his opponent to build a fortress.

Once again we divide the endgame into 3 elemental positions:

Game 2, Position 1 after 31... cxd6

This was where we left off from our doubled pawns series. Black had just undoubled his pawns, but retains control over the queenside light squares, semi-open b-file and the two bishops. For someone like Magnus Carlsen, that is more than enough to secure a win. Unless you are playing against a staunch defender like Karjakin!

Black first centralizes his king, maintains pressure on the backward b2 pawn, before seeking to create a new weakness in his opponent's kingside. In this way he can utilize the principle of two weaknesses to make life more difficult for Black.

Game 2, Position 2 after 45. Nd1

After probing around for several moves, Black has obtained what he wanted: A kingside pawn majority. This gives White two weaknesses on opposite wings to take care of: The b2 pawn and a potential passed pawn on the other wing. Meanwhile, his own pawn majority is rendered useless by the c4 pawn, while his knight is restricted by the enemy's powerful bishop pair. Although material is equal, Black is effectively one pawn up.

With 45... Be6 it would effectively guarantee Carlsen free reign on the kingside. However, he erred with the pawn push 45... f4?, releasing the tension too early. While the intention was to tie down White's pieces to stopping the pawn while his own king invades via b3, it gave Karjakin an opportunity to build a fortress with Nf2, Bd4 and Kd2-Kc1, stopping Black's king from entering the queenside.

Game 2, Position 3 after 60... Kb3

In the closing shots of this tough battle, Black looks on the verge of breaking through on b3. But after 61. Kc1, White has set up his fortress. His king stops any encroachment by his opposing counterpart, while bishop and knight form a defensive blockade around the centre and kingside.

Amazingly, Carlsen has no way to make any further inroads into Karjakin's fortress! Although the game continued all the way till move 94, it was essentially drawn after 61. Kc1.

We show the full stages of the endgame in all its glory:


What can we learn from this game?

  1. Utilize the principle of two weaknesses; in this case White's pressure on the b2 pawn and the threats of his kingside pawn majority gave him a huge advantage
  2. Freezing an enemy pawn majority is a powerful endgame tool; combining it with the advance of your own majority on the opposite wing can be decisive
  3. Avoid closing up the position when you have a bishop against the enemy's knight

...

With the conclusion of Rounds 3 and 4, the score was still even. But with Carlsen so close to gaining the lead, it was definitely no series of boring draws. Truly great defense by Karjakin, and we shall look at more selected games in subsequent articles!

Links:
Part 1: http://nushsblackknights.blogspot.com/2016/12/world-chess-championship-2016.html
Part 2: http://nushsblackknights.blogspot.com/2016/12/world-chess-championship-2016_17.html
Part 3: http://nushsblackknights.blogspot.com/2017/01/world-chess-championship-2016.html
Part 4: http://nushsblackknights.blogspot.com/2017/01/world-chess-championship-2016_30.html

Sources:
https://www.youtube.com/watch?v=SeBfGhAhFQA
https://www.youtube.com/watch?v=tWfFx2Pa6zU
https://www.youtube.com/watch?v=ULaFA5eZnJA
https://www.youtube.com/watch?v=FuEEiLOTfs4
https://www.chess.com/news/view/scissors-can-t-beat-rock-in-world-champs-round-4-3294

Thursday, December 8, 2016

A story of doubled pawns: Part 3

In Part 2 we talked about the weaknesses of doubled pawns. But before we jump to conclusions and demonize all these poor fellas, let's first look at the other side of the mirror, and find out if they can offer anything that's helpful.

Today, we will see how doubled pawns can be used as an asset instead of a liability. To start off, we recap from Part 1 what advantages doubled pawns can offer:

  1. Opening of files. When doubled pawns are formed an adjacent file has to be opened, and this can be exploited by your rooks.
  2. Square control. By far the greatest strength of doubled pawns lies in defense, as they control more squares than regular pawn chains.

One rule of thumb when playing with doubled pawns is to avoid pushing them whenever possible. Advancing the forward pawn relinquishes control over vital squares and opens up holes around them. Unless pushing them helps to undouble the pawns, control even more important squares upfront, or whatever other reason, try not to do so.

To illustrate the defensive abilities of doubled pawns-- and why they should preferably stay at their posts-- we take a look at the following position:

Position 1: Doubled pawns on the kingside

The above diagram is similar to Position 4 from Part 2, only that we have dropped additional pawns on c2 and f7. As long as the doubled pawns remain in their positions, Black cannot advance his kingside pawns against them and hope for a breakthrough, or infiltrate with his king.

However, if White pushes the pawns with g4 and h3, then he creates weak spots in his position that the enemy king can use for himself.


Position 2: Weak spots among the doubled pawns

Let's play as Black and see if we can make any headway against the "weak" doubled pawns on the kingside. You might see both sides making a few suboptimal moves in the game below, but they are played so as to demonstrate the characteristics of doubled pawns:


Additional Square Control

From the first example we saw how doubled pawns play a defensive role by covering squares that would otherwise have been occupied by the enemy. If we extend this to actual gameplay, doubled pawns situated in front of a castled king can offer additional protection, with greater control over the squares in front of the monarch.

So long as the rear guys don't stab their friends in front by mistake

Another way to exploit this power occurs when said foot-soldiers are located close to the centre. It is not uncommon for grandmasters to accept doubled pawns so as to exert greater influence over the centre, as seen in the next example.

In the following game, Black gets doubled pawns on the c-file. Instead of becoming targets of attack, however, they end up being a great asset by increasing Black's presence in the centre. Radjabov used them to create an outpost on d4, gaining space and cramping up the opponent's position.

The following article provides more games, where the side with doubled pawns exploits them to exert central dominance. A true testimony to Tarrasch's teachings on centre control!

"Son, I am proud"


Opening of files

When a pawn captures onto an adjacent file and forms doubled pawns, the original file is inevitably opened up. This is another valuable resource that can be used by friendly rooks.

The concept of occupying such an open file occurs in a few openings, such as the following variation of the Caro-Kann: 1. e4 c6 2. d4 d5 3. Nd2 dxe4 4. Nxe4 Bf5 5. Ng3 Bg6 6. Nf3 e6 7. Ne5!? Nd7 8. Nxg6 hxg6 (D)

Position 3: Doubled pawns with an open file for the rook

Black has doubled pawns, but has a beautiful half-open h-file for his rook. His plan is to castle queenside and bring his pieces over for a kingside attack, using the h-file as a springboard for the assault. The following game between two anonymous players is a good illustration of this:

One striking example of doubled pawns and the adjacent open file comes from Game 4 of the recently concluded World Championship Match. Carlsen had doubled isolated pawns on the queenside, but was able to take advantage of the half-open b-file -- and his light-square dominance-- to pressurize the opponent's position. This gave Carlsen serious winning chances throughout the game, and it was only after grim defense by Karjakin that the game was finally drawn.

We will examine this game in greater detail in our WCC 2016 series.


Other forms of compensation

This is a more generalized idea of the previous part. Apart from the adjacent open file, doubled pawns can be accepted if they come with some sort of compensation. In openings like the Ruy Lopez and Nimzo-Indian, one side gets a damaged pawn structure, but acquires the bishop pair as compensation. It boils down to whether he can open up the position to utilize his advantages, yet at the same time take the focus of battle away from his doubled pawns.

Our final game is a good showcase of how the two bishops balance out the apparent weakness of the doubled pawns:

...

To wrap up, doubled pawns are not always the devil of a game. They can offer valuable help by controlling extra squares, opening up files, or create other forms of compensation. So don't go around saying that doubled pawns are always bad... such hearsay is is reserved only for beginners!

So far we have focused mainly on the effects of doubled pawns in the opening and middlegame. In Part 4, we will look at how they can affect the endgame as well.

To be continued...

Links:
Part 1: http://nushsblackknights.blogspot.com/2016/11/a-story-of-doubled-pawns-part-1.html
Part 2: http://nushsblackknights.blogspot.com/2016/11/a-story-of-doubled-pawns-part-2.html
Part 3: http://nushsblackknights.blogspot.com/2016/12/a-story-of-doubled-pawns-part-3.html
Part 4: http://nushsblackknights.blogspot.com/2016/12/a-story-of-doubled-pawns-part-4.html
Part 5: http://nushsblackknights.blogspot.com/2017/01/a-story-of-doubled-pawns-part-5.html
Sources:
"Modern Chess Strategy" by Ludek Pachman
https://www.youtube.com/watch?v=1rTMfayZatI
http://www.thechessworld.com/learn-chess/2-middle-game/526-doubled-pawns-weakness-or-strength-part-2
http://300spartanwarriors.blogspot.sg/2016/06/classical-greece-and-ancient-greek_93.html

Thursday, December 1, 2016

World Chess Championship 2016 Highlights: Part 1

Yesterday the chess world concluded one of its most historic events of the year: The World Chess Championship 2016. This year saw Carlsen faced with his biggest challenge yet, for Karjakin was able to hold out throughout the classical games and even achieve a one-point lead (briefly) in Game 8. The results were finally decided in hair-raising tiebreakers where the Norwegian routed his opponent 3-1.

WCC 2016, Carlsen's toughest championship test

With so many instructive games in the past two weeks, I cannot resist going through some of them. Hence, I will dedicate a new series of articles to analysis of selected WCC 2016 games. Don't worry though, I haven't forgotten about wrapping up the doubled pawns series I started last month!

What better way to kick off than with one of the match-deciding games from the tiebreakers!

Karjakin, Sergei vs Carlsen, Magnus
World Chess Championship 2016 Tiebreakers Round 3

In the previous game, Karjakin escaped with a miraculous draw after sacrificing several pieces and pawns to force a stalemate. Going into the final two rounds, we will see whether he can continue his unbreakable spirit, or whether Magnus will finally wear him out.

1. e4 e5
2. Nf3 Nc6
3. Bb5 a6
4. Ba4 Nf6
5. O-O Be7
6. d3 b5
7. Bb3 d6
8. Nc3 O-O
9. a3 Na5
10. Ba2 Be6
11. b4 Nc6
12. Nd5

You may be wondering whether White could simply wreck Black's pawn structure with 12. Bxe6 fxe6. Yes, White does get doubled pawns, but they are not easily attacked in this closed position. In fact, they may even help Black by controlling more squares in the centre and opening up the f-file for his rook.

12... Nd4
13. Ng5 Bxd5

While damaging White's pawn structure Black has to give up his bishop pair, but this isn't particularly alarming since the two bishops cannot fully unleash their power in this closed position.

14. exd5 (D)

Position after 14. exd5

Not 14. Bxd5? giving up the bishop pair for nothing, and also losing a piece after Nxd5

14... Nd7

Making room for an f5 push, expanding on the kingside while keeping the centre closed. 14... c6 comes into consideration, giving Black's pawn centre some free reign. However, he wouldn't want to undouble White's pawns and open the centre for the bishop pair, so this plan is cast aside in favour of the main line.

15. Ne4 f5
16. Nd2 f4

Things are starting to go Black's way. While White has the bishop pair, one is blockaded by the enemy pawns, while the other babysits a friendly pawn on d5. This is why Carlsen chooses to keep the centre closed.

17. c3

Otherwise 17... f3 follows.

17... Nf5
18. Ne4 Qe8

Bringing reinforcements to the kingside.

19. Bb3

Since Karjakin can't do anything about White's plans for now, he tries to find counterplay on the other wing. Here, the aim is to push a4 and (hopefully) get the light-squared bishop onto a better diagonal.

19... Qg6
20. f3!? (D)

Position after 20. f3

A natural and solid looking move, preparing 21. Ra2/Rf2 as a response to 20... Nh4. But some consider this questionable: White's queen is cut off from interfering, and the e3 square becomes a tempting outpost for the enemy. For now only the bishop on f1 stands guard over it.

20... Bh4

White needs to be watchful of a potential bishop sacrifice on g3, which would open up the h-file and bring the pawn onto g3, covering the White king's escape squares. This is a common attacking motif against an undefended kingside.

21. a4 Nf6
22. Qe2 a5!

Magnus creates problems for his opponent, who was starting to run into time trouble.

23. axb5?

The wrong choice made under time pressure. This lets Black exchange on d4, weakening e3 and giving White multiple pawn weaknesses. After 23. bxa5 Rxa5 24. Ra2! bxa4 25. Rxa4 Rxa4 26. Bxa4 White has achieved what he wanted: Get some space for his bishops. While Black still has strong pressure on the kingside, at least White can give him some problems on the opposite wing.

23... axb4
24. Bd2 (D)

Position after 24. Bd2

Black chooses not to take the extra material, since he has a hanging rook and a vulnerable d4 square to take care of.

24. Rxa8 Rxa8 25. cxb4? Nd4! The extra material is worth nothing since it comes in the form of isolated doubled pawns.

24... bxc3
25. Bxc3 Ne3

With the bishop no longer covering e3 Black can brazenly step in. Karjakin's position is becoming very cramped, and the fact that he is down on time isn't helping at all.

26. Rfc1!

Setting up a trap. The key is that Black's king is under indirect fire by the light-squared bishop, which means the d5 pawn cannot be taken straightaway.

26... Rxa1

There are many ways Black could have gone wrong here:

  1. 26... Nfxd5? 27. Qxe3! fxe3 28. Bxd5+ Gaining a rook, bishop and pawn for the queen. But what is more important is that Black's attacking strength is severly reduced, and the e3 pawn will fall very soon.
  2. 26... Nexd5? 27. Nxf6+ is even worse for Black, for the pin ensures he remains a piece down after the exchanges.
  3. Finally, 26... Rab8? falls prey to a discovered attack: 27. Bxe5! dxe5 28. d6+ $1 Kh8 29. dxc7 Rbc8 30. Nd6 At the cost of his bishop White gets a powerful passed pawn.

27. Rxa1 Qe8

It seems weird to retreat from the kingside when you were putting so much pressure on it. But flexibility is a virtue of war, and here Black switches sights to attack the queenside weaknesses.

28. Bc4 Kh8

Stepping away from the line of fire. Now Black threatens to capture on d5.

29. Nxf6 Bxf6
30. Ra3

30. Bd2 with hopes of getting rid of the e3 knight fails after 30... e4! 31. Ra3 exf3 32. Qxf3 opening up the e-file as an invasion point for Black's queen. There is no way White can trade on e3 now, otherwise a passed pawn is born.

Black has the edge with his strong knight, and his position has less vulnerable points than White's. But White still holds the fragile line with his bishop pair. Can the world champion find a breakthrough here?

30... e4!

Sacrificing a pawn to gain entry.

31. dxe4

White is very happy to undouble his pawns, so why not?

31... Bxc3
32. Rxc3 Qe5! (D)

Position after 32... Qe5

The point of 30... e4, to clear the d5 square as a staging point for the invasion. Black's dark-square dominance is indisputable.

33. Rc1 Ra8
34. h3 h6
35. Kh2 Qd4
36. Qe1?

Cold-blooded engines would not hesitate to play the counter-intuitive 36. Ba2 temporarily halting Black's invasion of the 1st rank, but for a human to find this with less than 5 minutes on his clock would be too much to ask.

36... Qb2

Threatening a mate in one; the next move is forced.

37. Bf1 Ra2
38. Rxc7??

With seconds left on his clock, Karjakin makes his final error. But the endgame was already extremely difficult to defend.

38. Rb1 was the only defense; 38... Qf6 39. Be2 Black still maintains a huge advantage but has no immediate win.

38... Ra1 (D)
0-1

Position after 38... Ra1

White must give up the queen or face ... Nxf1+/Qxg2#.

With this win Carlsen gains a huge morale victory; he only needs a draw in his next game to defend his title!

Links:
Part 1: http://nushsblackknights.blogspot.com/2016/12/world-chess-championship-2016.html
Part 2: http://nushsblackknights.blogspot.com/2016/12/world-chess-championship-2016_17.html
Part 3: http://nushsblackknights.blogspot.com/2017/01/world-chess-championship-2016.html
Part 4: http://nushsblackknights.blogspot.com/2017/01/world-chess-championship-2016_30.html
Sources:
https://www.chess.com/news/view/carlsen-wins-rapid-playoff-defends-world-championship-7236
https://www.youtube.com/watch?v=eclStFntWGE
https://www.youtube.com/watch?v=VWWwfYNzrfs
https://www.youtube.com/watch?v=85RTfoI97oQ