Showing posts with label Conticello. Show all posts
Showing posts with label Conticello. Show all posts

Friday, May 30, 2008

Adventures in Sokolsky's Jungle

It's always a pleasure to discuss something you know nothing about and don't care that much about either. Whether 1.b4 e5 2.Bb2 Bxb4 3.Bxe5 Nf6 4.c4 0–0 5.Nf3 Nc6 6.Bb2 Re8 7.e3 d5 8.cxd5 Nxd5 9.Be2 Rxe3!? is correct or not will not have a great impact on my repertoire but the complications are nevertheless enjoyable.

In a recent entry my preliminary conclusion was that 10.fxe3 Nxe3 11.Qb3 Nxg2+ 12.Kd1 doesn't look like a clean winning line. Consequently it seems sensible to examine White's alternative king move, 12.Kf2. Even if alternatives have been tested, I will assume that 12...Bh3 (Dia) is the critical test. Black develops another minor piece while protecting his advanced knight.
13.d4

This looks natural.

a) White should avoid 13.Rg1? Bc5+.

b) Unsurprisingly 13.Bf1 also fails: 13...Bc5+ 14.Kg3 Qd7 15.Qc4 Nd4 16.Nxd4 Qg4+ 17.Kf2 (Gross-Grehl, corr 1991) 17...Qf5+! 18.Kg1 Re8 and Black is winning.
c) 13.Bc4 Qe7 (13...Bc5+ 14.Kg3 Qd7 15.Bxf7+ Kh8 16.Qc4 Rf8–+ Alvarez-Roldan, corr 1998) 14.Bxf7+ Kh8 15.Bd5? Bc5+ 16.Kg3 Qd6+ 17.Kxh3 Nf4+ also wins for Black Nebe-Vorlop, corr 1988.

d) 13.Kg3 looks suspect and 13...Qd7!? probably is sufficient:

d1) 14.Ng5 Bd6+ 15.Kf2 Qf5+ 16.Nf3 (or 16.Bf3 Bc5+ 17.Ke2 Qxg5) 16...Bc5+ 17.Kf1 Nf4+ 18.Ke1 Re8 and Black wins.

d2) 14.Ne5 Bd6 15.d4 Nxe5 16.dxe5 Be7 17.e6 Bxe6 18.Qd3? Bd5 was winning for Black in Seifert-Nebe, corr 1991.

d3) 14.Qc4 b5 15.Qxb5 Bd6+ 16.Kf2 Rb8 17.Rc1 Rxb5 18.Bxb5 Qf5 –+ Gross-Grehl, corr 1992.

d4) 14.Ng1 Bd6+ 15.Kf2 Bc5+ 16.Kg3 Bxg1 17.Rxg1 Qd6+ 18.Kxh3 Nf4+ 19.Kg4 Nxe2

e) 13.Rd1 Qe7 14.Ba3 (14.Ng1? Bc5+ 15.d4 Nxd4 16.Rxd4 Qh4+ 0–1 Zschalich-Leisebein, corr 1987) 14...Re8 (14...Nd4!? 15.Qd3 Bxa3 16.Nxa3 Nxe2 17.Qxe2 Qxa3 with advantage to Black could be an improvement) 15.Bf1 g5 16.Bxb4 Nxb4 17.Na3 g4 18.Re1 Nxe1 19.Rxe1 Qc5+ 20.d4 Rxe1 21.Bxh3 Re2+ 22.Kxe2 gxf3+ 23.Qxf3 and White was slightly better in Zschalich-Preussner, corr 1997.

13...Qe7 (Dia)

This is the critical moment. White is relatively free to improve his position but nothing looks particularly convincing.

14.Ne5

a) After 14.Bc4? Na5 15.Bxf7+ Kh8 Black was winning in Gedigk-Grehl, corr 1990.

b) 14.Nbd2 is strongly met by 14...Bxd2 15.Nxd2 Nxd4 16.Qxh3 Qxe2+ 17.Kg3 f5 18.Rhf1 (18.Qxg2 f4+ 0–1 Ritter-Reyes, corr 1996) 18...f4+ 0–1 Oakes-De Smet, corr 1992.

c) 14.Na3?! Re8 15.Ne5? Nxe5 16.Qxh3 Nf4 was winning for Black in Perrson-Grehl, corr 1989.

d) 14.Rg1!? deserves a look.

e) 14.a3 should be taken seriously as it has been tested by one of the real experts: 14...Re8 15.Bc4 Na5 16.Qxb4 (16.Bxf7+ Kh8 17.Qd5 Qe2+ 18.Kg3 Ne3 –+) 16...Qe3+ 17.Kg3 Qf4+ 18.Kf2 Qe3+ 19.Kg3 h5 –+ Trokenheim-Ronneland, Sweden 1994.

14...Nxd4

14...Nf4!? may be an improvement. 15.Qxf7+ Qxf7 16.Nxf7 Nxe2 17.Nh6+ gxh6 18.Kxe2 Re8+ is clearly better for Black.
15.Qxf7+ Qxf7+ 16.Nxf7 Nxe2 17.Ng5 Bc5+ 18.Kxe2 Nf4+ (Dia)

Black still has only got three pawns for his rook but White's king is exposed and his rooks are exposed in their corners.

19.Kd1?!

Giving back the exchange with 19.Kf3 Bg2+ 20.Kxf4 Bxh1 looks fairly balanced but Black may have less losing chances.

19...Rd8+ 20.Kc2?

This seem to lose. 20.Nd2 doesn't look safe at all and I suspect a good PC programme would find something for Black if given some time and gentle guidance (but 20...Bg4+ 21.Kc2 Bf5+ 22.Nge4 Be3 23.Rhd1 Rxd2+ 24.Rxd2 Bxe4+ 25.Kd1 Nd3 26.Bc3 b5 is only a little better for Black).

20...Bf5+ 21.Kb3 h6 0–1 Zschalich-Poetzsch, corr 1987 (22.Nf3 Rd3+ –+)

Conclusion:

Based on available games and some quick checks by Fritz and Rybka, 12.Kf2 looks even less convincing than 12.Kd1. It probably will pay for both sides to examine alternatives to 11.Qb3 - that is 11.Qc1 and 11.Qa4.

Wednesday, May 21, 2008

A New Orang Utan in Town

I have very rarely played the Sokolsky opening (also known as the Orang Utan opening) as it doesn't lead to the kind of positions I enjoy to play as White. That doesn't necessarily mean it leads to bad positions and I have always had a certain interest in the opening and some of the original positions that can arise.
Now there is a new book on the opening available. The reviews so far haven't been too favorable so I am waiting for a chance to browse the pages at a chess book stand but I suppose I eventually will buy it.

Here is the Table of Content:

4 Bibliography
5 Introduction
11 The Sokolsky Gambit
35 1b4 e5 2Bb2 Bxb4
48 Black Plays ...e5 and ...d6
73 Queen's Indian Systems
100 Black Plays ...d5 and ...e6
121 Black Plays ...d5 and ...Bf5/Bg4
143 1 ...c6, 1...f5 and Unusual Moves
171 Index of Complete Games

If you too are still skeptical to the book you may want to see this interesting discussion at the ChessPublishing forum before you order (unless you are interested in re-incarnation flame wars you will do well to fast-forward to page 3).

In his review (in German) at Niggemann, Martin Rieger points out that one of the critical lines is quite superficially handled:

1.b4 e5 2.Bb2 Bxb4!? 3.Bxe5

This is the quintessential Sokolsky variation. White gets a central pawn in return for his b-pawn but allows Black a certain lead in development.

3...Nf6 4.c4

It's possible for White to speed up development by delaying this move and giving priority to the development of his kingside. However, this (or 4.Nf3 followed by 5.c4) is White's most popular as it makes it likely that White will be able to exchange his c-pawn for Black's d-pawn, enlarging his numerical superiority in the centre.

4...0–0 5.Nf3 Nc6!?

From a purely positional point of view, this looks premature. Now Black must rely solely on his piece play to compensate for White's central dominance. Most theoretical manuals recommend 5...Re8 and White probably should avoid 6.e3 d5 7.cxd5 Nxd5 8.Be2 (8.Bb2 Nc6 may transpose to the mainline below) 8...Rxe5! 9.Nxe5 Qf6 when 10.f4? is met with 10...Nxe3 -+.

6.Bb2 Re8 7.e3 d5 8.cxd5 Nxd5 9.Be2

It's not easy for White to improve on this, a3 and ...Ba5 doesn't seem to change too much but there certainly are sub-variations where it could make a difference.

9...Rxe3!? (Dia)

This controversial sacrifice has mainly been tested in correspondence games. If nothing else it's a fascinating starting point for analysis.

10.fxe3 Nxe3 11.Qb3!?

This apparently is Conticello and Lapshun's (C&L) attempted refutation. If this proves OK for Black, there still is 11.Qc1?! and 11.Qa4 to deal with.

11...Nxg2+ 12.Kd1

There also is 12.Kf2!? but again that's only necessary to investigate if C&L's mainline fails to convince.

12...Be6 13.Qd3 (Dia)

13...Qxd3!?

It's easy to forget that exchanging queens is an options after sacrificing a rook. This is Rieger's suggested improvement over 13...Qe7 which is the only move I could find in my databases (and which scores rather poorly). It would be interesting to know whether it's an invention of his own or if it can be found in specialist literature. Lapshun - Sinn, World op (Philadelphia) 2003 continued 14.Nd4 Nf4 15.Nxc6 bxc6 16.Qd4 Bb3+ 17.axb3 Qxe2+ 18.Kc2 1–0.

14.Bxd3 Bg4 15.Be2

15.Be4 Re8 16.h3 Bh5 seems no better:

a) 17.Bd5 Rd8 18.Bxc6 bxc6 19.Kc1 Bxf3 –+.

b) 17.d3 Rxe4 18.dxe4 Bxf3+ 19.Kc1 Nf4 and Black's advantage is obvious.

15...Nf4 16.Rf1

Again it's hard to find a real improvement:

a) 16.Rg1 h5 17.Nd4 (17.Rf1) 17...Nxe2 18.Nxe2 Re8 19.Rg2 Bc5 20.Nbc3 Bf3 =+.

b) 16.Nd4 Nxe2 17.Nxe2 Re8 18.Re1 f5!? (18...Bc5) 19.a3 (19.h3 Bh5) 19...Bd6 20.Nbc3 (20.d4 f4 -/+) 20...Nd4 21.d3 Bxh2 and Black is probably winning.

16...Nxe2 17.Kxe2 Bc5 (Dia)

This position may be crucial for the evaluation of one of the Sokolsky mainlines.

18.Kd3

Here Rieger gives 18.Bc3 Re8+ 19.Kd3 b5! and claims that Black is winning. The position is hard to evaluate but it seems White's king escapes and the position after 20.Kc2 b4 21.Bb2 Bxf3 22.Rxf3 Nd4+ 23.Bxd4 Bxd4 24.Nc3 bxc3 25.dxc3 Bc5 looks fairly equal.

18...Rd8+ 19.Kc4

White attacks the bishop. 19.Kc3 looks safer but then it will still take White several moves to co-ordinate his pieces and 19...b5 looks quite promising for Black.

19...Be6+

Also 9...Bb6 20.d4 Be6+ 21.Kd3 Nb4+ 22.Kd2 looks playable. White's winning chances must be rather limited after e.g. 22...c5.

20.Kxc5 Rd5+ 21.Kc4 Re5+

21...b5+ 22.Kc3 Rc5+ 23.Kd3 Bc4+ 24.Ke3 Bxf1 is not too different from the main continuation.

22.Kc3

22.Kd3 Bf5+ 23.Kc4 Be6+ 24.Kd3 Bf5+ is a perpetual as 25.Kc3? Rc5+ 26.Kb3 Bc2+ 27.Ka3 Ra5 is mate.

22...Rc5+ 23.Kd3 Bc4+ 24.Ke3 Bxf1

The position is unbalanced with Black having three pawns for a piece but chances look fairly equal.

Conclusion:

These lines are very hard to analyze but I cannot see that 11.Qb3 Nxg2+ 12.Kd1 lead to a convincing advantage for White and both players must investigate 12.Kf2 and possibly White's 11th move alternatives.

I will return with a Sokolsky bibliography at some point. In the meantime I can only recommend Marek Trockenheim's online Sokolsky Encyclopaedia. There's a huge amount of information there and it's quite well organized in a way. Yet it's not really easy to utilize it. You will find some games with the above lines here.

Addendum June 3rd.

Steve Giddins' review for British Chess Magazine points out a strange slip:

'I noticed only one major editorial lapse, albeit an embarrassing one – games 75 and 76 are actually the same game, annotated quite differently, and with different conclusions as to Black’s losing move!'

I wonder if this is somehow connected to John Elburg's observation that parts of the book is directly translated from Sokolsky's book:

'included are also the best of the great Sokolsky himself all directly translated from Sokolsky’s well known b4 openings book from the 1960s.'

Could it be that this is a Sokolsky game annotated by Sokolsky as well as by Lapshun/Conticello? I suppose I will have to buy the book in order to find out.