Saturday, November 30, 2013

Tragedy of a fianchettoed bishop

So having learned the Sicilian Dragon, KID, Larsen Attack, and all other random openings featuring a fianchettoed bishop, you might probably be well aware of the power of such a bishop in an attack against the castled king. But a fianchettoed bishop can have its weaknesses too; sitting at the side of the board, it can easily become a sitting duck should its path along the long diagonal get blockaded by enemy (or even friendly) pawns. The following game shows how this may lead to disastrous consequences:

Opponent vs Checkerboard 5
Children's Day Chess Challenge 2013


1. f4 Nf6
2. Nf3 e6
3. b3 Be7
4. Bb2 b6
5. e3 Bb7 (D)


Played without much realization of what will be to come. In several of my earlier games I had played the Old Queen's Indian with much success against irregular openings, much thanks to the solid and flexible nature of the pawn structure. However, I had yet to test it against a strong kingside attack, which will soon turn out to be the critical test of the setup.

6. Be2 d6
7. O-O Nbd7
8. d3 h6
9. Nbd2 c5
10. c4 O-O
11. h3 Nh5

To hit g3, gaining a tempo. My opponent had plans for the kingside, so of course he did not want this.

12. Qe1 Rc8
13. g4 Nhf6
14. Qg3 (D)


Here he comes. The activity of his kingside pieces, coupled with both the upcoming pawn avalanche and HIS fianchettoed bishop on b2, is more than enough to let me know that a major assault is upcoming.

14... Nh7
15. e4 Bf6!

When defending, the best strategy will be to exchange off the opponent's pieces to weaken the force of his attack. The b2 bishop was the best target here since it was hovering over the vulnerable g7 square.

16. Rab1?!

Fritz prefers the variation 16. e5 dxe5 17. fxe5 Bg5

16... Bxb2
17. Rxb2 (D)


17... Qe7

Now after some helpful analysis by Fritz, I feel that a much better option for me would have been to launch the pawn break immediately with 17... f5! After the variation 18. g5 (18. e5 dxe5 19. fxe5 f4 20. Qf2 leads to the same consequences, while 18. exf5 exf5 19. gxf5 Qf6 also helps to free my b7 bishop and bring my pieces over to the kingside quickly) 18... hxg5 19. fxg5 f4 White's attack is blunted. Although I still have the problem of trying to free my b7 bishop (which is still being hemmed in by the e5 pawn), at least my position is much less cramped than the one after the text move.

18. h4 f6
19. Rf2 e5?

The wrong break at the wrong time! After 19... f5 20. g4 h5 where the threat of fxe5 followed by d5 could still give me chances to free my b7 bishop. Now after the text move, White responds a move which leads to the permanent imprisonment of my bishop:

20. f5! (D)


20. fxe5 dxe5 removes the momentum from White's pawn avalanche.

A swift glance at the position can be enough to tell that things are not going well for me. White controls most of the space in the centre, which allows him to swiftly mobilize his pieces over to the kingside for the attack (his king, despite being on the kingside, is not getting in the way due to the space in the centre). Most of my pieces are in dug-in defensive positions, which is not that bad altogether since I can meet my opponent's threats...

Only except that I am a piece down. Look over to the fianchettoed bishop on b7-- I had placed it there in the opening without much thought of the fate that would befall it, and now one can tell that it has been literally cut off from the main action by White's pawn chain in the centre. To free it would cost several tempi (and moving lots of blocking pieces out of the way), which by then White would probably already have broken through.

Thus with the fianchettoed bishop sitting there and unable to participate in the defense of the kingside, I am as good as a piece down.

20... Kf7

I could not just sit there and watch White overrun my position-- when the command post is under fire His Majesty must evacuate to a safer place.

21. g5 hxg5
22. hxg5 Ke8

22... fxg5 23. Rh2 Rh8 24. Rxh7 Rxh7 25. Nxg5 Kg8 26. Nxh7 Kxh7 was the better alternative, but my bishop is still a prisoner on b7.

23. Nh4! Rg8
24. Bh5+ (D)
1-0


I stopped recording here; as the game continued I actually managed to evacuate my king successfully to the Queenside, but by then White had already broken through with his "extra piece" and won material.

As such, let this game be a reminder to self and everyone here that a fianchettoed bishop is not always an advantage. While it can prove to be a strong attacker when in control of the long diagonal, it can also become easily cut-off from the game, especially when the centre is closed.

Wednesday, November 27, 2013

A simple case of zugzwang: The trebuchet

In highly complex endgames it is always useful to steer the game towards basic endgame positions that you know-- opposite-colour bishops, Lucena and Philidor's positions, King+Pawn vs King, just to name a few-- so that the seemingly difficult position becomes a simple problem.

So let's take a look at the following basic position:


A quick look should be enough to tell one thing-- whoever to move is in zugzwang. Whichever king moves first will be unable to defend his own pawn, thus allowing the enemy king to gain both the pawn and the Opposition. So for example if it is Black's turn to move, then after 1... Kg5 2. Kxe5 Kg6 3. Ke6 Kg7 4. e5 White wins since his king is in front of the pawn and Black cannot gain the opposition.

In fact, this is such a well-known basic endgame position that it has a name: The Trebuchet

You want some of these?

The Trebuchet looks so damn easy to understand, I know most of us will wave it off as trivial and move on to concentrate on other important topics. But just to keep in mind, having a firm understanding of such simple positions like these can be helpful even when it comes to a complex situation like this:

White to move: Who's winning here?

Without having any prior knowledge many amateurs would probably panic at this position, but now with a basic understanding of the Trebuchet one should be able to play it out easily: The side who wins is the one who can make first diagonal contact with the central pawns and thus attain a winning Trebuchet position.

So Black, with his king closer to the pawns, should not find it difficult to secure the win here:

1. Kxb6 Kxg3 2. Kc5 Kf3!

Don't be a dunce and play 2... Kf4?? where after 3. Kd5! Black is now on the losing side of the Trebuchet

3. Kd5 Kf4

And we have the same position as in our first diagram, where White has been forced into zugzwang


And thus we can clearly see that in positions where a Trebuchet is imminent, the winning side is the one who can get his king to make first diagonal contact with the Trebuchet pawns. With this in mind, one will be sound enough to avoid blunders like 2... Kf4?? in our previous example.

And so do remember to add this concept to your arsenal of endgame knowledge. Like the Lucena and Philidor's Positions in rook endgames, it is a useful one to remember when it comes to handling complex pawn endgames.

Sources:
http://www.ucantalk2me.com/cooltalk/trebuchets/science-behind-trebuchet-attack.html
"Silman's Complete Endgame Course" by Jeremy Silman

Monday, November 25, 2013

Chess Camp Curiosities: Part 3

Well let us now end off this section with our third and final game... also a more serious one. Still, the lessons learned from this game are worth noting down


1. d4 d5
2. Bf4 Nc6!?

The main line continues either 2... e6 or 2... c6

3. Nf3 Nf6
4. e3 Bf5
5. Bd3 Bxd3
6. cxd3!? (D)


A novelty-- at the cost of his pawn structure, White gets the open c-file as well as the threat of 7. e4, taking control of the centre. 6. Qxd3 would have been safer but less ambitious

6... e6
7. O-O Bd6
8. Ne5 Bxe5
9. dxe5 Nd7
10. d4 O-O
11. Nd2 Ne7
12. Qg4

White seizes the initiative. The threat of pushing e4 is hanging in the air.

12... Ng6
13. Bg5 Qe8
14. Rac1 c6
15. e4! h6
16. Be3 (D)


The other variation is 16. Bh4, where White still has space to retreat his bishop

16... f5!

Black finally responds with a strong counterthrust. After 17. exf6 Nxf6 (17. Qd1? leads to 17... f4!) 18. Qg3 dxe4/Nxe4 he can consolidate his position with an extra pawn, but White can exploit the hole on d6 with the maneuver Nc4-Nd6. The position is at least equal.

17. exf5?!

Dropping a piece

17... exf5
18. Qh3 f4
19. e6 Nf6

20. Rfe1 fxe3
21. Rxe3 Ne7

White probably thought he could compensate for his lost piece with a central passed pawn, but Black's blockade of the pawn proves otherwise. The knight cannot be chased away easily.

22. f4 Qg6
23. Rg3 Qh5
24. Qxh5 Nxh5 (D)
0-1

You shall not pass!

The passed pawn is going nowhere. With an extra piece, picking off the pawn is only a matter of time for Black.

Edit: I decided to add the following picture as an afterthought:

Too hot for ye?
Links:
Part 1: http://nushsblackknights.blogspot.com/2013/11/chess-camp-curosities-part-1.html
Part 2: http://nushsblackknights.blogspot.com/2013/11/chess-camp-curiosities-part-2.html

Saturday, November 23, 2013

Chess Camp Curiosities: Part 2

Well if you thought Game 1 from my previous article was hilarious, then you haven't seen Game 2. As quoted by Khaarthik (or was it someone else? I can't remember correctly), "Fritz is gonna have a very fun time analyzing this game!"


1. e4 e5
2. Nf3 Nc6
3. d4 exd4
4. Bc4 Bc5
5. c3 dxc3?!

Had Black known what was to befall him in the next move, he would probably have declined the gambit and  continued with a developing move like 5... Nf6

6. Bxf7+!? (D)

YOLO!

6... Kf8

Surprisingly, Black has nothing to lose by accepting the sacrifice now-- after the variation 6... Kxf7 7. Qd5+ Ke8 8. Qxc5 d6!? 9. Qxc3 Nf6 Black has managed to catch up in development, even though White retains a slight advantage over here (possibly because Black is no longer able to castle naturally)

7. Bxg8 Rxg8
8. Nxc3 d6
9. O-O

And now White has a clear lead in development, similar to Game 1

9... Bg4
10. h3 Bh5 (D)


11. Qd5

A much better move proposed by Fritz was 11. g4! where after 11... Bf7 12. Ng5 White has a strong attack. This, coupled with Black's awkward kingside position, will be enough to throw Black into disarray

11... Bxf3
12. Qf5+ Qf6
13. Qxf3 Qxf3
14. gxf3 Nd4
15. Kg2 Ke7
16. Nd5+ Kd7
17. Be3 c6
18. Bxd4 Bxd4
19. Nc3 g5 (D)

The tides are changing...

After a series of exchanges in the middlegame, Black has actually solved most of his problems, and has even managed to launch a counterattack of his own. White's messed-up pawn structure on the kingside is no longer to his advantage.

20. Rad1 Be5
21. Kh1 Raf8
22. Rd3 h5
23. Rg1

23. Rfd1? leads to 23... g4 24. hxg4 hxg4 and Black is on the verge of breaking through the kingside

23... Rf4
24. Ne2 Rh4
25. Kg2 g4!
26. hxg4 hxg4
27. Kf1 (D)


Black still has a slight advantage over here, but if White can evacuate his king in time from the danger zone he can play into an equal endgame.

27... Rh3
28. Rb3 Kc7
29. fxg4 Rxb3
30. axb3 Bxb2
31. f4 d5
32. exd5 cxd5

And indeed the game is now equal-- both sides have passed pawns of their own, but have sufficient strength to blockade each other. It is now a matter of who can march his passed pawns to the promised land first.

33. f5 d4
34. Nf4 Kd7? (D)


Under the pressure Black probably missed 34... Bc1 35. Nd3 Bg5, where the blockade of both White's passed pawns ensures an eventual draw. Now,

35. g5 Ke7

And Black misses the chance again; 35... Bc1 could still have stopped the pawns!

36. f6+ Kf7
37. Ke2 Bc3
38. Kd3 Re8

38... b6 was the move suggested by Fritz, but even so White now has a lasting advantage.

39. Rg3 b5?
 40. Nd5 Bb2
41. g6+ Kf8
42. Nc7

The other variations suggested during post-game analysis were 42. Ne7 Rb8 and 42. Rh3!? Re3+

42... Re3+
43. Rxe3 dxe3

Black tries his best to advance his own pawn but it is evident that White is winning the race

44. f7 Bg7
45. Ne6+! Ke7
46. Nxg7 (D)
1-0


White will simply pick off the e3 pawn with his king, before moving over to escort his own pawns to the 8th rank.

Links:
Part 1: http://nushsblackknights.blogspot.com/2013/11/chess-camp-curosities-part-1.html

Carlsen vs Anand, the aftermath

Firstly, congrats to Carlsen on his victory yesterday. I know most of you are supporters of him, so you must be feeling really great.

Just don't catch a cold, yeah?

But yeah, by now (after all those posts I've made on FB) it should be obvious to you that I'm an Anand fan. And if you ask me why I support him, my reply would be that... I'm really not sure. It just so happened that while I was watching the matches, I had this unexplainable feeling that I wanted Anand to win.

And of course I've been disappointed 3 times. The first time Anand was completely outplayed. The second time he made a bad mistake in the endgame, and the third time he just blundered altogether.

"At the end of the day my play in the match was a big disappointment. I didn't manage to achieve any of the things I tried to aim for."
-- Vishy Anand


May be indeed a great disappointment for both Anand as well as all chess fans in India. But at the end of the day, what matters is whether he can pick himself up after this defeat and move on with his career. Because after all that's what chess-- or in matter or fact, any other sport-- is all about. While the desire to win is an important one, it's a fact that you cannot win all the time in life; sometimes, you lose. And chess teaches you to cope with these losses, and turn them into valuable lessons for your future games.

"Vishy has been the world champion for so long, one of the greatest of all time. I'm honored to have played the match with him and of course very, very happy to have gotten the better of him. I really hope he'll be back in the Candidates."
-- Magnus Carlsen


And of course, Carlsen's next critical test will come up in no time-- whether he can defend his title as long as, if not longer, than Anand has successfully defended it.

Sources:
http://www.chess.com/news/breaking-magnus-carlsen-16th-undisputed-world-champion-of-chess-1065

Friday, November 22, 2013

Chess Camp Curosities: Part 1

Well the really fun thing about amateur-level play is the amount of mistakes which we make that allows the game to swing wildly in either direction. While admittedly grandmasters do blunder once in a while (like how Anand just blundered in yesterday's match!), but definitely not as much as our level!

So now I'm gonna release the 3 games played during Activity 3 of our chess camp over here one by one. Here's the first one-- and see the mistakes that both sides make that really decide the game!


1. e4 e5
2. Nf3 Nf6
3. Nxe5 d6
4. Nf3 Nxe4
5. d4 d5
6. c4 c6
7. Nc3 Bb4
8. Qb3 Bxc3+
9. bxc3 (D)


9... dxc4?

After this move White will recapture with the bishop, thus gaining a huge lead in development. Black would have been better off by completing development with something like 9. O-O

10. Bxc4 O-O
11. O-O Nd6
12. Bd3 h6
13. Re1 b6
14. Ne5 Re8
15. Ba3 Be6
16. Qc2 f5?! (D)


Drops a pawn, but according to Darryl "Black gets compensation by exchanging his (bad) bishop for the opponent's active one". Fair enough o.o

17. Bxd6 Qxd6
18. Bxf5 Bxf5
19. Qxf5 Rf8
20. Qg4 Qf6
21. Re2 Na6
22. Nd7

Stronger was 22. Qd7, where Black is helpless against the invasion of the 7th rank. Now, Black can simply escape the knight fork with...

22... Qf5
23. Qxf5 Rxf5
24. Re7

Nevertheless, White is still winning over here.

24... c5
25. dxc5 Nxc5
26. Nxc5 Rxc5
27. Rc1 Ra5
28. Rc2 Rc8
29. f3 Ra3
30. Kf2 a5
31. Re3 b5
32. Ke2 b4 (D)


33. Kd2

33. c4! would have been better, giving White a passed pawn. Now, Black has amazingly solved most of his problems and played into an equal endgame, although he is still a pawn down.

33... bxc3+
34. Rexc3 Rcxc3
35. Rxc3 Rxa2+
36. Rc2 Rxc2+
37. Kxc2 (D)
0-1


The game continued for quite some time, but Black's outside passed pawn eventually proved decisive. How quickly the tides of war swing!

I'll post the next two games soon in future articles.

Friday, November 8, 2013

Carlsen vs Anand, Tal Memorial 2013

For those who are still unaware, the World Chess Championship 2013 will be held from 7th November 2013 to 28th November 2013, in Chennai, India. It features World Number 1 Magnus Carlsen as the challenger against Vishwanathan Anand, who is the current World Champion.

While everyone is getting hyped up over what is probably the greatest tournament in recent years, let us take a look at what happened at their last encounter, during the Tal Memorial in June.

Over here, the World Champion was completely outplayed by the World Number One; Carlsen gained the edge by first trading off the dark-squared bishops, before making preparations to play e4 and achieve a central breakthrough. While Anand attempted to defuse the threats in the centre by repositioning his bishop from b7 to f5, Carlsen felt that"It's a decent enough positional move, it just doesn't work. At least as far as I could see."

Carlsen, Magnus vs Viswanathan, Anand
Tal Memorial 2013


The annotations and commntary have been provided by both ChessVibes and Carlsen himself after the game, so I'll use them over here:

1. d4 Nf6
2. c4 e6
3. Nc3 Bb4
4. e3 O-O
5. Nge2

Carlsen: "I thought I'd play a line that he hasn't faced in a long time and I thought that hopefully he wouldn't be too prepared for that."

5... d5
6. a3 Be7
7. cxd5 Nxd5
8. Bd2 Nd7
9. g3 b6
10. Nxd5 exd5
11. Bg2 Bb7
12. Bb4 (D)


Carlsen: "Since I've put all my pawns on dark squares it makes sense to exchange this bishop first."

12... Nf6

After the variation 12... c5 13. dxc5 bxc5 14. Bc3 and Carlsen commented that Anand's "hanging pawns are more likely to be weak than a dynamic strength, because his pieces are not particularly active and mine are well positioned to meet whatever he's going to do in the center."

13. O-O Re8
14. Rc1 c6
15. Bxe7 Rxe7
16. Re1 Qd6

Carlsen expected 16... Ne4 17. Nf4 Nd6 "and I can never really push the pawns on the queenside because the knight is very well place to meet that, but after 18. Nd3 followed by putting pressure on the c6-pawn White is already playing for two results, which is an achievement."

17. Nf4 Bc8 (D)



 Carlsen: "Now he's trying to reposition the bishop to f5 after which his problems would be much less. It's a decent enough positional move, it just doesn't work. At least as far as I could see."

18. Qa4 Rc7

Carlsen: "The logical move, preparing ...Bf5."

After 18... Bd7 19. Qb4! Carlsen commented that "in general the exchange of queens is favourable to White." Because after the line 19...  Ne8 20. Nd3 f6 21. Qxd6 Nxd6 22. Nb4 Rc8 23. Nxc6 Bxc6 24. Rxc6 Rxc6 25. Bxd5+ White is slightly better here.
 
19. f3! (D)


Carlsen: "Now the problem is I change plans. I really cannot see a good continuation here for him. If I manage to push e4-e5 he will have serious positional problems."

19... Be6?!

Carlsen: "I was thinking about 19... Qd8 20. e4 dxe4 21. fxe4 Bd7 and now White shouldn't rush with (22. e5 Nd5 23. Nxd5 cxd5) but play 22. Qb3! thus keeping all the threats"

20. e4! dxe4
21. fxe4 Qd7
22. d5!

The tactical refutation. If 22. e5 Nd5 and Black beats off White's threats

22... cxd5
23. Qxd7 Rxd7
24. Nxe6! (D)


24. exd5 Bf5 (24... Nxd5 25. Nxd5 Bxd5 26. Red1) 25. Re5 Bg6 "and while his position is not impressive here either, I think he can definitely fight on."-- Carlsen

24... fxe6
25. Bh3!

Carlsen: "I suspect he missed this, after which it's pretty much gone. There are tactical problems everywhere."

25... Kh8 (D)


25... Re8 26. exd5 Kf8 27. Bxe6 Rde7 28. Rf1 Rd8 29. Rf5 "and it's still very difficult to suggest anything decent for Black." -- Carlsen

26. e5 Ng8
27. Bxe6 Rdd8
28. Rc7 d4
29. Bd7 (D)
1-0

Final position after 29. Bd7

Carlsen: "I just go 30.e6 and take the pawn; there's really nothing he can do."

...

So it's no surprise that Carlsen is the clear favourite in this tournament. However, the veteran Anand is still a very formidable opponent, having more experience in head-on play as compared to his Norweigan opponent. Many exciting games feature ahead!

Source:
http://www.chess.com/news/carlsen-crushes-anand-at-tal-gelfand--nakamura-lead-3973

Monday, November 4, 2013

Bishops of similar colour in the endgame: Part 3

In this final part on endgame positions featuring similar-coloured bishops, we will take a look at what hahpens happens when the stronger side has an advantage of 2 pawns. It is actually quite simple, provided you get the idea correct:

Black to play and win

Looks like a dead win for Black isn't it? And yes, it is! The reasoning behind this is simple: Unlike similar position where the stronger side only has the advantage of one pawn, over here the weaker side cannot force a draw by sacrificing the bishop for one of the pawns. Doing so will only allow the remaining pawn to promote. So all Black has to do is...

1... Ke3 2. Ba4 Bf3!

And then Black can play d3-d2-d1=Q with no worries, assured of the fact that should his pawn be captured on d1, he can still invest in the other pawn on g4.

Now let's make some small adjustments to the current position, and see whether this will make a difference:

No quick win here!

And suddenly the game turns into a dead draw: Once White is able to trade off his bishop for the e-pawn, the endgame will simplify into a rook pawn + wrong coloured bishop drawn position!

1... Ke2 2. Bg5 and Black can't chase off White's bishop without losing the h pawn (you can play it out if you're not convinced), as both White's king and bishop work together to stop both pawns at the same time. After this, the drawing technique is the same as we have discussed in Part 1.

However, do note that if we were to make some adjustments to the position, then things would turn out very differently:

  1. If White's king were far away-- say, on a8 instead of g2, then Black has better winning chances as he can push both his pawns without fear of interference from the enemy king. The defending bishop alone cannot stop both pawns at the same time.
  2. If both bishops were light-squared instead of dark-squared bishops, then Black can simply just trade off his e-pawn for the enemy bishop, after which he will win easily as his bishop controls the h-pawn's queening square.
...


Now suppose we place the split pawns together such that we now have king + bishop + two connected passed pawns against a king + bishop position:

Black to play and win

And of course we may think: Such a no-brainer, obviously Black will win easily over here! Once again you're right, but I want to go through this because we have to look out for some nasty surprises which the weaker side may spring!

Even though they are connected passed pawns, Black's pawns alone cannot make the perilous journey to the back rank with the enemy king and bishop in the way. Thus, Black's plan consists of using both his king and bishop to support the advance of the pawns, while at the same time keeping a lookout for the traps that White can use to force a draw. (Use the Knightvision viewer at the bottom of the article if you can't visualize)

1... d4+

The point is to make sure Black does not lose control over any of the squares in front of the enemy king. The pawns cover the dark squares while the supporting bishop covers the light squares, thus preventing White's king from coming close

If 1... e4?? then White forces a draw by setting up a blockade with 2. Kd4, after which Black cannot play 2... Kf5 due to 3. Kxd5, while after the continuation 2... Bf7 3. Bh3+ Kd6 4. Bf5 (threatening 5. Bxe4) Black's pawns aren't going anywhere.

2. Kd2 e4
3. Bg2 Ke5

It is important to support the pawn advance with the king!

4. Bh3 e3+

Once again, not 4... d3? because of the blockading move 5. Kd3. In this case Black still has winning chances (because the White bishop is restricted by the Black pawns) but it is much longer and more complicated, so for now let's say that you will be wise enough to avoid the blockade trap.

5. Ke2 Kf4
6. Bd7 d3+

And Black slowly pushes White to the edge of the board. Note both bishop and king are working together to support the advance of the two pawns.

7. Ke1 Bh5
8. Kf1 e2+
9. Kf2 d2 (D)
0-1

Position after 9... d2

And the pawns cannot be stopped from promoting.


Relatively straightforward, but keep in mind of the following:

  1. Don't let the weaker side trade his bishop off for both your pawns
  2. Use both your pawns and bishop to keep control over all the squares around it, so that the enemy king cannot set up a blockade of both pawns
  3. Always use your king to support the pawn advance

And with that, I close up my series on similar-coloured bishops in the endgame. Although these are relatively simple positions that only involve a few pieces, similar positions will occur often in your games and thus I recommend that you look through all 3 parts again until you get a firm understanding of the concept.

Links:
Part 1: http://nushsblackknights.blogspot.com/2013/10/bishops-of-similar-colour-in-endgame.html
Part 2: http://nushsblackknights.blogspot.com/2013/11/bishops-of-similar-colour-in-endgame.html

Source:
"Silman's Complete Endgame Course" by Jeremy Silman

Saturday, November 2, 2013

Bishops of similar colour in the endgame: Part 2

Before we continue on in our study of similar-coloured bishop endgame positions, I want to make sure that you have fully digested all the material which I have shared in Part 1. If not, go back and read through it again: http://nushsblackknights.blogspot.sg/2013/10/bishops-of-similar-colour-in-endgame.html

Now we have looked at many examples featuring the battle between a king + bishop vs a king + bishop + pawn on the 7th rank. Now, using the ideas which we have learnt in Part 1, let us learn how to successfully advance a pawn that is as far back as the 5th rank.

White to play and win

Let us have a short analysis of the position... both bishops are on similar coloured squares, so that's a plus for the stronger side (White). Black's king is close to the enemy pawn and directly opposes White's king, which makes White's job of winning more challenging. However, also note that the pawn is a wing pawn; and based on what we've learnt in Part 1, this means good winning chances for White.

Thus, all White has to do is to push his pawn successfully to a6 without it getting captured; once he has done that, then the advance to a7 can be done without fear of interference from the enemy bishop, and then we will have a winning endgame position with a wing pawn on the 7th rank. (If you have no idea what has been said so far, go back and read through Part 1 again)

The question now is... how is White going to do this?

Let's take a look (once again, see the KnightVision viewer at the bottom of the page if you can't visualize):

1. Bb7 Bd3

Black tries to do his "shuffle" trick

2. Ba6 Be4
3. Bb5 (D)


White has successfully chased Black's bishop away from the longer diagonal. Now, Black has to attempt to switch to the shorter, a6-c8 diagonal.

3... Bb7
4. Bd7!

Black is in zugzwang

And obviously not 4. Kxb7?? Kxa5! with an instant draw.

Looking at the position, it is not hard to tell that Black is in zugzwang-- his bishop has no free squares along the crucial a6-c8 diagonal. Now, any king move allows 5. Kxb7, while any bishop move along the h1-a8 diagonal allows the pawn to be advanced safely up the board. And yes-- this is similar to the idea that we have learnt in Part 1, where the weaker side will run into zugzwang if one of the diagonals has less than two free squares for his bishop to shuffle on.

4... Bf3
5. a6 Be4
6. a7 (D)

"Victory is ours!" shouts White

And here we have, the theoretically won position with a wing pawn on the 7th rank. Black's bishop is unable to switch diagonals to screen the queening square, and there is no defense to 7. Bc6

6... Bh1
7. Bc6
1-0


White's plan was simple: First he chased off the defending bishop from the long diagonal, and forced him to switch defense to the fatally short a6-c8 diagonal. Then, by exploiting the fact that the a6-c8 diagonal has less than 2 free squares for the defending bishop to move on, he forced Black into zugzwang, and advanced his pawn to victory. Almost similar to what we've learnt in Part 1!

In Part 3, we will continue to look into other endgame positions featuring bishops on similar-coloured squares.

Links:
Part 1: http://nushsblackknights.blogspot.com/2013/10/bishops-of-similar-colour-in-endgame.html

Sources:
"Silman's complete endgame course" by Jeremy Silman

Friday, November 1, 2013

The story of Iron Tigran: Part 4

Hope your exams went well! And now while everyone's partying after their papers are over, let's get back to business here.

By now you must already be well versed with the concept of blockade given that I have already shown you so many examples in previous articles. But if you thought that blockade was needed only to defend against an enemy breakthrough, then you're quite mistaken-- now, sit back and let Petrosian demonstrate how to utilize a blockade to carry out a successful attack.

In the following game, a successful knight blockade on c5 allows Black to gain dominance over the dark squares, before achieving a breakthrough on the queenside.

Bisiguier, Arthur vs Petrosian, Tigran
New York 1954


1. d4 Nf6
2. c4 c5
3. Nf3 cxd4
4. Nxd4 Nc6
5. Nc3 e6
6. g3 Bc5
7. Nb3 Be7
8. Bg2 O-O
9. O-O d6
10. e4 Ne5
11. Qe2 Qc7
12. Nd2 a6
13. b3 b5 (D)


Black is able to expand on the queenside without fear due to the pin on the c-file.

14. f4 Nc6
15. Bb2

If White grabs the pawn with 15. cxb5 then 15... Nd4 16. Qc4 (16. Qd3? Qxc3! wins a piece due to the threat of a fork on e2) 16... Qa7 with the threat of discovered check gives Black the initiative. But now, Black must do something about the threat on b5-- the most common continuation will be 15... bxc4, in an attempt to undermine White's control of the centre (and the recapture 16. bxc4? drops a piece to 16... Qb6+). But after 16. Nxc4, White maintains his central advantage due to his firm control over the d5 square, coupled with his more centralized knights.

Hence, Petrosian decides on an alternate route:

15... b4!

This move serves several purposes-- it denies White the c4 square for one of his knights, drives off the other knight from its post, and provides a blockade square on c5 for the Black knight. Now, Petrosian begins to devise his plan-- shift his knight to the c5 outpost, before advancing his pawns down the queenside to open the files for his rooks.

16. Nd1 a5
17. Ne3

White could trade off the knight with 17. Bxf6?! before it gets to the c5 square. However, after 17... Bxf6, he would cede control of the central dark squares to Black.

17... a4
18. Rab1 axb3
19. axb3 Ra2 (D)


While there are no immediate threats to White's position, the thought of an enemy rook nestled on the second rank is certainly an unnerving thought. Bisiguier now launches an attack on the kingside, but all the time he has to keep a constant lookout in case the Black rook suddenly decides to break through (with let's say, ...Rxc2!?).

20. g4 Nd7
21. g5!

Preventing Black from exchanging bishops with 21... Bf6!, after which Black would have an even greater control over the d4 square.

21... Re8
22. Kh1 Nc5 (D)


Stage 1 of the plan is complete-- the knight has reached its base on c5. Notice that it can never be dislodged by a White pawn, and exerts great influence over the squares e4, d3 and b3. Certainly a perfect outpost for a blockade! Now Petrosian begins Stage 2-- increasing his control over the dark squares by moving his other knight to d4. To do this he has to play the e6-e5 pawn break, but first he has to make a couple of preparatory moves.

23. h4 Qd8

To allow for ...e6-e5 without White being able to play Nd5 and attack the queen

24. Rf3 Bf8

The bishop gets out of the way of a possible f5-f6 advance, and also helps to clear the e-file for the rook.

25. Rg3 e5!
26. f5 Nd4 (D)


If not for this counterblow, White would have been able to launch a successful kingside attack with moves like Nd5, followed by an avalanche of his kingside pawns (h4-h5, g5-h6, etc.). This highlights the reasoning behind the previous moves 23... Qd8 and 24... Bf8-- they prevent White from gaining tempo by hitting the Black Queen with Nd5 which would have helped in White's attack. This example of prophylaxis is one that highlights Petrosian's brilliant defending skills.

Also, notice how while in the process of defending against White's threats, Black has also been able to exert a greater influence over the dark squares in the centre.

27. Qf1

If 27. Bxd4 then 27... exd4 28. Nd5 Bxf5! wins the e4 pawn. Now, White has to abandon his kingside attack and make a number of odd queen moves in order to prevent himself from losing material. Meanwhile, Black carries on with his plans on opening up the queenside.

27... Ndxb3
28. Nxb3 Nxb3
29. Qe1 Nc5
30. Qxb4 Bb7!

With dominance established on the dark squares, Black proceeds on to the next stage of his plan-- to attack the weak e4 and c4 pawns. First he attacks the e4 pawn to force 31. Nd5, before proceeding on to the e4 pawn as his next target (which will become weak as a result of Nd5). This helps to clear the way for a pin along the b-file, which will ultimately culminate in a breakthrough on the queenside.

31. Nd5 Ra4
32. Qd2 Bxd5!

Removing the White Queen from the defence of the b4 square. All other moves lose more quickly: 33. cxd5 is met my 33... Nxe4, while 34. exd5 allows 34... Rxc4

33. Qxd5 Rb4
34. Bf3 Qa8

Exchanging queens will kill off any of White's last hopes for a kingside attack

35. Qd2 Qb7
36. Rg2 Rb8 (D)



A triple battery along the b-file-- a queenside breakthrough is inevitable. Now, Black's threat of 37... Na4 (winning the bishop) forces White to give up the e4 pawn, and his position quickly crumbles after that.

37. Bd1 Qxe4
38. Bc2 Qxc4
39. g6 Rxb2
40. gxh7+ Kh8
41. Rbg1 Qxh4+
42. Rh2 Qf4 (D)
0-1

Final position after 42... Qf4

Petrosian's plan was to use his central blockade to exert a greater influence over the central dark squares, upon which he could capitalize to attack the weak points within his opponent's position. At the same time, his prophylactic skills enabled him to beat off his opponent's chances of counterplay on the kingside. His plan culminates with the breakthrough of the heavy pieces on the queenside.

And with that, I end of my series on Tigran Petrosian, the master of strategy and defence. I hope his games can continue to be a source of inspiration to you in the future, alongside other players such as Fischer and Alekhine.

Links:
Part 1: http://nushsblackknights.blogspot.com/2013/09/the-story-of-iron-tigran-part-1.html
Part 2: http://nushsblackknights.blogspot.com/2013/10/the-story-of-iron-tigran-part-2.html
Part 3: http://nushsblackknights.blogspot.com/2013/10/the-story-of-iron-tigran-part-3.html

Source:
"The Giants of Strategy" by Neil Macdonald