05 September 2015

Commentary: 2015 U.S. Championship, Round 9 (Ni - Nemcova)

The following commentary game continues the series from this year's 2015 U.S. Championship.  The round 9 game between Viktorja Ni and Katarina Nemcova features a struggle in the English with a number of typical strategic choices and positional characteristics, even if it went out of the database relatively quickly.
  • White opens up the queenside and gains space, following the standard plan of pushing the b-pawn, but this is a two-edged sword; in this game, Black could have more effectively exploited the queenside opening (on the a- and b-files) for her own purposes.  
  • White made an unusual decision to develop early and exchange her dark-square bishop.  She eliminated an often dangerous kingside piece for Black (the Nf6) but this of course came with drawbacks (such as giving Black the two bishops).  
  • The choice of where to put White's queen (on d2 or c2) is also a typical problem that I've run across.  From my own experience, it seems that it's easy to make the wrong choice, even if (or especially because) it is not an obvious error.
  • Black's decision to delay initiating her kingside counterplay (with ...f5) may have cost her time and the opportunity to more effectively pressure White.
  • The choice by Black to exchange White's fianchettoed bishop is also worth studying for both sides.  The White player in the English, for example, should have a good idea of when it is advantageous to initiate the exchange on h3 in such situations.
For those interested, the original commentary on the game by GM Josh Friedel can be found on the ChessBase site (as well as the news item for what most people paid attention to in Round 9, the infamous arbiter decision to forfeit GM Wesley So).

Ni, Viktorija (2188) - Nemcova, Katerina (2279)

Result: 1/2-1/2
Site: Saint Louis
Date: 2015.04.10
[...] 1.c4 e5 2.¤c3 ¤f6 3.¤f3 ¤c6 4.a3 White has many playable options on move four of the English Four Knights variation. This one is more in the spirit of a reversed Sicilian, but can also transpose to more standard English positions (as happens in the game). 4...g6 this is a standard English way to develop the bishop and scores relatively well for Black (around 47 percent).
4...d5 would be the way to directly challenge White, in the style of the Open Sicilian (reversed). However Black only scores 42 percent in this line.
5.d3 ¥g7 6.¥g5 this isn't found in many high-level games and is an accelerated development of the dark-square bishop. 6...h6 7.¥xf6 consistent, otherwise White loses time retreating the bishop. The game is now already out of the database. 7...¥xf6 8.g3 O-O 9.¥g2 ¥g7 the bishop retreats to protect h6 and get out of the way of the f-pawn. 10.O-O White now has a rather standard-looking English position, as does Black. 10...d6 11.¦b1 White's typical plan is to use the b-pawn advance to expand on the queenside and push the Nc6 away, leaving the long diagonal open for White's bishop. 11...a5 Black chooses to (temporarily) challenge the b-pawn advance, rather than move forward with other development and preparing counterplay on the other wing. The text move will result in opening the a-file for Black's rook, after the pawn exchange. 12.b4 axb4 13.axb4 ¥e6 14.¤d5?! while it's a key principle of the English to occupy d5 with a knight when advantageous, it's often difficult to understand when it is best to do so. Here the knight move is premature, as it would allow Black to block the long diagonal more effectively.
14.b5 ¤e7 15.£c2 followed by Nd2 is a standard and good approach.
14...£d7 with the evident idea of playing ... Bh3 as a follow-up. This is rather slow, however.
14...¤e7!? and now 15.¤xe7 £xe7 16.¤d2 c6 17.b5 d5³ is good for Black. For example 18.bxc6 bxc6 and it's clear White has no threats, while Black has a strong center and better prospects on the queenside as well.
15.¤d2 this now allows the bishop to support the Nd5, which is in a strong position.
15.b5 ¤e7 16.¤d2 would also be fine. If the Nd5 is exchanged, White would have doubled d-pawns, but the strength of the d5 pawn would be compensation for that. 16...¥xd5 17.cxd5
15...¦a2 not a bad move, but the resulting continuation is a little awkward for Black.
15...¦a3 is the rook move preferred by Komodo 8. The difference with the text move is that the rook on a3 controls c3 and cannot be challenged by a White knight.
15...¤d4 is another possibility. The knight otherwise is going to be placed rather awkwardly after White's b-pawn advance. One sample continution: 16.e3 ¥xd5 17.cxd5 ¤b5
16.b5 ¤d8 essentially forced, in order to protect the b7 pawn. 17.¤b3 the idea behind this move is apparently to support an eventual c5 advance. This eventually comes to fruition, but the knight is nevertheless not optimally placed.
17.¤c3 is the obvious move here, hitting the Ra2 and clearing the long diagonal for the bishop.
17...c6 18.¤b4 (18.¤c3 is also still possible.) 18...¦a8 19.bxc6 bxc6 20.£d2 it's sometimes difficult in the English to figure out the best square for developing the queen. In any case, it's important to get the rooks connected and maximize the queen's utility. Here the choice is between d2 and c2. On d2, the queen has open diagonals (c1-h6 and a5-e1) but it's not clear if they can ever be utilized. On c2, it might better support the queenside and would leave d2 open for the Nb3. 20...¥h3?! Black follows up with her original idea of exchanging the Bg2.
20...f5 is perhaps more to the point, getting Black's counterplay on the kingside going sooner.
21.¦fd1?! this effectively loses a tempo for White.
21.¥xh3!? an English player needs to know when to exchange the Bg2 like this. While Black's queen always looks threatening on h3, without the support of a knight or advanced pawns it will be less effective. 21...£xh3 22.c5 taking advantage of the Nb3's presence 22...d5 23.¦a1
(21.¦a1 is another alternative, challenging the Ra8.) 21...¥xg2³22.¢xg2 f5
22...¤e6!? would get the knight back in the game, connect the rooks and again control c5.
23.c5 evidently this was the idea behind the positioning of the Nb3. 23...d5 24.d4 e4 Black by this point has a stronger center and more space, so White needs to turn her attention to trying to contain Black's threats. 25.f4 this can be a key defensive move for White in these position types. 25...exf3 26.exf3 f4 27.g4
27.gxf4?27...¤e6 28.¤d3 £f7ยต and White's shattered kingside pawns will not provide an adequate defense.
27...¤e6 28.¦e1 ¦a3?! making this rook more active isn't a bad idea, but again this is not the best square for it on the a-file.
28...¦a4 exerts indirect pressure on d4 and can't be chased off by a knight.
28...¦fb8!? gets the other rook into the game effectively and illustrates how White's opening of the queenside can also be a weakness, with Black's rooks looking much better placed.
29.¤c2 ¦aa8?! this makes the maneuver just a waste of time. (29...¦a4) 30.£d3 (30.¤a5!? threatening Rb7 is an interesting idea.) 30...£f7 31.¦e2 at this point White has blunted Black's initiative and can start manuevering again. 31...h5 a good practical move by Black, as White does not find the best continuation. 32.h3?! this sort of defensive move is often instinctual, as it appears more solid than exchanging on h5. However, in that event White will be the one controlling the g-file, so it's actually better. (32.gxh5 gxh5 33.¦g1 followed by Kh1 and White is fine.) 32...hxg4
32...£f6³ threatening to penetrate on the kingside, looks more effective.
33.hxg4 ¦ae8 this removes Black's possibility of making threats on the a-file. If Black wants a rook on e8, Rf8-e8 makes more sense, since the f-pawn is already overprotected. 34.¦be1 White again looks fine, now that Black's threats have dissipated. 34...¥f6?! this is too slow and allows White some initiative. (34...£f6!?) 35.¤b4 now the knight is not tied to the d-pawn and can make threats of its own. 35...¤d8 the only way to protect the c-pawn without losing something somewhere else. 36.¦xe8?! this is not forced and is a good example of how it is often better to maintain tension and even increase it, rather than release it prematurely.
36.¤a5 would be the most challenging for Black, who would then have to find 36...¥h4 to keep things equal.
36...¦xe8 37.¦xe8 £xe8 38.£d2 at this point the position looks equal/drawn, so perhaps White simply wanted to head for a draw earlier. 38...¤e6 39.¤a5 ¤xd4 one of multiple drawing continuations. White will win the d5 pawn with her queen, but this leaves the back ranks open for Black's queen to penetrate and give perpetual check. 40.¤axc6 ¤xc6 41.£xd5 ¢g7 42.¤xc6 £e2 43.¢g1 £e1 44.¢g2 £e2 45.¢g1 £e1
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2 comments:

  1. Hey, I noticed that you switched to the Aquarium game display. What version are you using?

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    1. It's Aquarium 2015, using the "Web Export -> iBook HTML for blog" option. Unfortunately the standard "HMTL for Blog" export option still screws up the main blog page - as I've experienced before with other Aquarium versions. However, I like this format, since it pairs a large board with scroll protect with the large format notation and comments. It also works well with mobile platforms and gets away from Flash, so I expect it'll be my new standard for the foreseeable future.

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