Sunday, September 9, 2007

The Zwaig Variation II

There are indications that the critical line in Zwaig's variation (1.e4 e5 2.Nf3 Nc6 3.Bb5 a6 4.Ba4 b5 5.Bb3 Na5 6.0–0 d6 7.d4 f6) may be 8.Bxg8 Rxg8 9.b4!?. Tisdall describes this move as 'too ugly to be true'. But although I cannot claim to understand why, it has been the choice of some of the best prepared players ever to face 7...f6.

9...Nc4 (Dia)

10.Nbd2 Nxd2

10...Nb6!? has been played by a correspondence World Champion and should be taken seriously: 11.Qe2 Be6 12.Rd1 c6 13.dxe5 dxe5 14.Nc4 Nd7 (14...Qc7 15.Nxb6 Qxb6 16.a3 c5 +=) 15.Nd6+ Bxd6 16.Rxd6 Bc4 17.Qe3 (17.Qd1 Qc7 18.Be3 Nf8 19.a4 may be even stronger) 17...Qc7 18.Rd1 a5 19.Nd2 Be6 20.bxa5 Rxa5?! (20...Kf7! Oim; 20...Qxa5) 21.Qe2 Ke7 22.Nb3 Ra4 23.Be3 += Stern-Oim, corr 1994.


11.Bxd2 c6 (11...c5 12.c3 Bg4 13.Re1) 12.c3 Be6 13.Be3 Be7 14.Nd2 (14.a4) 14...a5 15.Qc2 g5?! (15...axb4 16.cxb4 Qd7 17.Nb3 +=) 16.a4 Qb8 17.axb5 Qxb5 18.c4 +- Helmers-O.Moen, Norway 1975.

11...Bb7 12.Re1 Qd7

12...a5 is probably weaker: 13.bxa5 c5 14.dxc5 dxc5 15.Qe2 Qxa5 16.Nxe5 0–0–0 (also 16...fxe5 17.Qh5+ g6 18.Qxe5+ Kf7 19.Rd1 is clearly better for White) 17.Nf3 Bd6 18.Bb2 and White's advantage was beyond doubt in T.Ernst-Gausel, Ostersund 1992.

13.Bb2 Be7

Tisdall suggests that 13...0-0-0 is worth consideration.

14.a4 f5 15.axb5 fxe4 16.bxa6

An interesting computer-aided line goes 16.Ng5 Qg4 17.bxa6 Rxa6 18.Rxa6 Qxg2+ 19.Kxg2 e3+ 20.Nf3 exd2 21.Rea1 Bxa6 22.Nxd2 Bb7+ 23.f3 Kd7 24.dxe5 dxe5 with equality.

16...Rxa6! 17.Ng5

17.Rxa6 is met by 17...exf3! planning ...Qg4 with a mating attack.

17...Rxa1 18.Bxa1?

18.Rxa1 Qg4 19.Nh3 Qxg2+ 20.Kxg2 e3+ 21.Kg3 exd2 22.dxe5 h5 23.f4 dxe5 24.Bxe5 g5 –+.


Black is close to winning already. White has nothing to oppose the light-squared bishop.

19.Nh3 (Dia)


A nice demonstration of the power of Black's light-square play.

20.Kxg2 e3+ 21.Kg1?!

21.Kf1 may be slightly better but after 21...exd2 22.Rd1 e4 23.Rxd2 d5 White has no satisfactory reply.

21...exd2 22.Rd1 g5 23.dxe5 g4 24.Nf4 Bg5 25.Ne2 Be4 26.exd6 Bxc2 27.dxc7 Kd7 0–1 T.Ernst-Tisdall, Gausdal 1993.


Anonymous said...

Nice post.

Maybe it will be possible to make the games replayable by using Chess Publisher ( The new version seems to be a lot better.

Sverre Johnsen said...

Thanks for your tip.

I will have a look at it and give it due consideration. However, I am not so sure that I like to include the variations and annotations in a chess applet - actually I like to have a pure text editor. Maybe I will go for the old version with just the moves if I can make it work.