The Tichomirov-Poznyanskaya middlegame position analysis (1966)

The Tichomirov-Poznyanskaya middlegame position analysis (1966)

Tichomirov and Poznyanskaya published a paper in 1966 in which they studied the eye movements of human chess players who were initially shown a certain middlegame position from a chess game. Herbert Simon has used the results of this study in his own research.

What can we learn from modern-day analysis of this position? A deep analysis shows that this position is full of dynamic possibilities - especially for the move 1...Ng4. Which ones will be powerful enough to drive the continuation of the game? Black can sacrifice a pawn (or more) for an attack. The reader should look beyond the simple Re8 or Bf5 moves. The clever 1...c4 is met by 2.h4 or 2.Kb1. This is a tactical position - one that we would expect the current set of chess programs to handle well. We set up the position and tell the machine to investigate the top moves. Using another machine, we investigate alternates to the predicted mainlines.

The Tichomirov and Poznyanskaya middlegame position, black to move

Komodo 10.1 TB6 smart syzygy

After 1...Ng4 2.Rhf1 Ne5

+0.19/52    3.d6 Be6 4.Qxe4 c4 5.f4 Nd3+ 6.Bxd3 cxd3 7.f5 Rac8 8.f6 Bh8 9.Rxd3 Qb5 10.h4 Rfd8 11.Rfd1 Qa5 12.d7 Rc4 13.Rd4 Rxc3+ 14.bxc3 h6 15.Bxh6 Bxf6 16.R1d3 Qxa2 17.Ra4 Qe2 18.Qf3 Qe1+ 19.Qd1 Qxd1+ 20.Rxd1 Bb3 21.Rxa7 Bxd1 22.Kxd1 Rxd7+ 23.Kc2 Bxh4 24.Bf4 f5 25.Be5 Bd8 26.Bd4 Kf7 27.Kd3 Ke6 28.Ra4 Kd6 29.e4 fxe4+ 30.Kxe4 Re7+ 31.Kd3 Re6 32.Rb4 Kc6 33.c4 Bc7 34.Rb5

+0.16/48    2. ... Ne5 3.f4 exf3 4.gxf3 Bh3 5.Rfe1 Qa5 6.e4 b5 7.f4 b4 8.fxe5 bxc3 9.Qxc3 Qxc3+ 10.bxc3 Bxe5 11.Be7 Bxc3 12.Bxf8 Bxe1 13.Bxc5 Rc8 14.Rxe1 Rxc5+ 15.Kb2 Kf8 16.Kb3 Bd7 17.Bc4 Bb5 18.Bxb5 Rxb5+ 19.Kc4 Rb2 20.h3 Ke7 21.e5 Rxa2 22.Rb1 Ra4+ 23.Kc5 Ra5+ 24.Kd4 Ra4+ 25.Ke3 Ra3+ 26.Ke4 Ra4+ 27.Kf3 Ra3+ 28.Kf4 Rxh3 29.Ra1 Ke8 30.Rxa7 Rd3 31.d6 Rd5 32.Re7+ Kf8 33.Kg5

+0.14/46    3.Qxe4 c4 4.Qh4 Bd7 5.d6 Rac8 6.Bf6 Nd3+ 7.Bxd3 cxd3 8.Bxg7 Kxg7 9.Qf4 f6 10.Rd2 Be6 11.Rfd1 Bc4 12.Qd4 Qxd4 13.exd4 Rc6 14.Re1 Rxd6 15.b3 Ba6 16.Re7+ Rf7 17.Rxf7+ Kxf7 18.d5 b6 19.f4 Rd7 20.Rd1 h6 21.g3 Rd6 22.a4 Rd7 23.Kd2 Bb7 24.Rc1 Ke7 25.Kxd3 Bxd5 26.Nxd5+ Rxd5+ 27.Ke4 Ke6 28.Rc6+ Rd6 29.Rxd6+ Kxd6 30.f5 g5 31.Kd4 h5 32.h3 g4 33.hxg4 hxg4 34.b4

+0.14/47    2...Ne5 3.Qxe4 c4 4.Qh4 Bd7 5.d6 Rac8 6.Bf6 Nd3+ 7.Bxd3 cxd3 8.Bxg7 Kxg7 9.Qf4 f6 10.Rd2 Qa6 11.Kb1 Rc4 12.e4 Ba4 13.Nxa4 Rxa4 14.a3 Rd8 15.Rc1 Rc4 16.Rxc4 Qxc4 17.Qg3 Qxe4 18.Qxd3 Qxd3+ 19.Rxd3 Kf7 20.Kc2 Ke6 21.Re3+ Kxd6 22.Rd3+ Ke7 23.Rxd8 Kxd8 24.Kd3 Kd7 25.g4 Kc6 26.Kd4 Kd6 27.h4 b6 28.f3 f5 29.gxf5 gxf5 30.h5 Ke6 31.h6 Kd6 32.a4 Ke6 33.b4 Kd6

+0.18/47    1...Ng4 now +0.15/50 2.Bxg4 Bxg4 now:

a) +0.11/58    3.Be7 Rfe8 4.d6 Qa5 5.Rd2 b5 6.Nxe4 Bf5 7.Kd1 c4 8.f3 Bxb2 9.Qxb2 Bxe4 10.fxe4 c3 11.Qb3 cxd2 12.Rf1 Rxe7 13.dxe7 Qa4 14.Qxa4 bxa4 15.Kxd2 Re8 16.Rb1 Rxe7 17.Rb4 a3 18.Rb3 Rxe4 19.Rxa3 Re7 20.Ke2 f5

b) +0.07/54    3.Rd2 Qa5 4.Be7 Rfe8 5.d6 b5 6.Nxe4 Bf5 7.Kd1 Qxa2 8.Ke2 Qe6 9.Nxc5 Qxe7 10.Qxf5 gxf5 11.dxe7 Rxe7 12.b4 f4 13.Rb1 fxe3 14.fxe3 Rae8 15.Rb3 Bf8 16.Rd5 Rc7 17.Rg5+ Kh8 18.Ra3 Bd6 19.h3 Bxc5 20.Rxc5 Rxc5 21.bxc5 Rc8 22.h4 Rxc5 23.Rxa7 Kg7 24.Kf3 Rf5+ 25.Kg3 Rf1 26.Rb7 Rb1 27.h5 Rb2 28.e4 Kf6 29.Kf4 Rf2+ 30.Ke3 Rxg2 31.Rb6+ Kg5 32.Rxb5+ Kh6 33.Rd5 Rb2 34.Kf4

+0.26/39    1...Bd7 2.h4 h6 3.d6 Rad8 4.Bxf6 Bxf6 5.h5 Kg7 6.hxg6 fxg6 7.Nxe4 Bf5 8.Bf3 Rfe8 9.Rd2 h5 10.Qa4 Be5 11.Rhd1 Qb4 12.Qxb4 cxb4 13.Rd5 b6 14.Rb5 Rc8+ 15.Kd2 Bxe4 16.Bxe4 Bxd6 17.Rd5 Rxe4 18.Rxd6 Re7 19.Ke2 Rc5 20.R1d2 Rg5 21.g3 Ra5 22.b3 Rc5 23.Rd7 Rc7 24.Rxe7+ Rxe7 25.Rd4 Rc7 26.Kf3 Kf6 27.Rd6+ Kg5

+0.42/39    1...h6 2.Bxf6 Qxf6 3.Nxe4 Qe5 4.Nc3 Bd7 5.g3 Rad8 6.h4 Rfe8 7.e4 Qe7 8.Rhe1 Bxc3 9.Qxc3 Qxe4 10.Bb5 Qg4 11.Rxe8+ Rxe8 12.Bxd7 Qxd7 13.h5 Qd6 14.hxg6 fxg6 15.Qd3 Kg7 16.f4 Re7 17.Kb1 b6 18.a3 a5 19.Ka1 Re8 20.Ka2 Rd8 21.Rd2 Re8 22.f5 Qf6 23.g4 Re5 24.fxg6 Qxg6

+0.44/39    1...Re8 2.Bc4 h6 3.Bh4 Bg4 4.Rd2 Qb4 5.Qb3 Nd7 6.d6 Qxb3 7.Bxb3 Bxc3 8.bxc3 Be6 9.Ba4 Rab8 10.Bxd7 Bxd7 11.Be7 b5 12.Kb2 Kg7 13.f3 exf3 14.gxf3 Bc6 15.e4 Rb7 16.Rg1 Rd7 17.Rdg2 Rb8 18.h4 a5 19.Rc1 Ra8 20.Rd1 Rc8 21.h5 g5 22.Kb3 b4 23.cxb4 cxb4

+0.47/39    1...c4 2.Kb1 Bd7 3.h4 Rac8 4.h5 h6 5.Bxf6 Qxf6 6.Nxe4 Qa6 7.hxg6 fxg6 8.d6 Ba4 9.Qd2 Bxd1 10.Rxd1 Rfd8 11.Qd5+ Kh8 12.Rd2 Qc6 13.Bg4 Qxd5 14.Rxd5 Rc6 15.d7 Bf6 16.Nd6 c3 17.bxc3 Kg8 18.c4 h5 19.Bh3 Be7 20.Nxb7 Rb6+ 21.Rb5 Rb8 22.Rxb6 axb6 23.Be6+ Kf8 24.Bd5 Bd8 25.Bc6 Ke7 26.Kb2 g5 27.Kc3 h4 28.c5 bxc5 29.Kc4 g4 30.Nxc5

After 1...Ng4 2.Bh4

+0.00/44 2...Ne5 3.Qxe4 Bf5 4.Qf4 Rae8 5.f3 c4 6.e4 Bd7 7.d6 Re6 8.Kb1 Nd3 9.Bxd3 Bxc3 10.Qc1 Bd4 11.Bxc4 Rc8 12.b3 Rxd6 13.Qh6 Bg7 14.Bxf7+ Kh8 15.Qf4 Qc5 16.Bc4 Rb6 17.Qc1 Qe5 18.Rxd7 Qa1+ 19.Kc2 Qxa2+ 20.Kd3 Rxb3+ 21.Bxb3 Qxb3+ 22.Ke2 Rc2+ 23.Qxc2 Qxc2+ 24.Rd2 Qc4+ 25.Rd3 Qc2+ 26.Rd2

Deep Rybka4.1 x64, older analysis

************deep runs**********

[+0.20] d=30 1...Bd7 2.h4 Ng4 3.d6 Qa5 4.Nxe4 Qxa2 5.Bxg4 Bxg4 6.f3 Bf5 7.g4 Bxe4 8.fxe4 b5 9.d7 b4 10.b3 Qa6 11.Rd5 Bc3

[+0.31] d=30 1...h6 2.Bxf6 Qxf6 3.d6 Bf5 4.h3 b5 5.Rd2 b4 6.Nb5 Rfd8 7.Nc7 Rab8 8.g4 Be6 9.Nxe6 Qxe6 10.Bc4 Qf6 11.Qxe4 Rxd6 12.Rxd6 Qxd6 13.Rd1 Qf6 14.Rd2 Rf8 15.h4 a5

[+0.33] d=30 1...Ng4 2.Rhf1(note 4) Ne5(note 1) 3.Qxe4(note 5) c4 4.Qh4 Bd7 5.d6 Nd3+ 6.Bxd3 cxd3 7.Rxd3 Bb5 8.Rfd1 Bxd3 9.Rxd3 Qa6 10.Qe4 Rfe8 11.Be7 Bxc3 12.bxc3 Rad8 13.Qd5 Rd7 14.e4 Qa3+ 15.Kd1 h6 16.g3 Qb2

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[+0.18] d=29 1...Ng4 2.Rhf1(note 4) Ne5(note 1) 3.d6(note 5) Be6 4.Qxe4(note 6) c4(note 2) 5.Qc2 Rfc8 6.Be7(note 3) Qc5 7.e4 Nc6 8.f4 Nxe7 9.dxe7 Qxe7 10.f5 Bxc3 11.bxc3 Bd7 12.f6 Qe8 13.Rd4 Rd8 14.Qd2 Bc6 15.Bxc4 Rxd4 16.Qxd4 Qxe4

[+0.20] d=30 1...Bd7 2.h4 Ng4 3.d6 Qa5 4.Nxe4 Qxa2 5.Bxg4 Bxg4 6.f3 Bf5 7.g4 Bxe4 8.fxe4 b5 9.d7 b4 10.b3 Qa6 11.Rd5 Bc3

[+0.27] d=29 1...Bd7 2.Kb1 Rfe8 3.d6 Rad8 4.Rd2 h6 5.Bh4 Qa5 6.Nd5 g5 7.Bg3 Nxd5 8.Rxd5 b6 9.Bc4 b5 10.Rxc5 Rc8 11.Bb3 Rxc5 12.Qxc5 Rc8 13.Qd5 Be6 14.d7 Rd8 15.Qxe4 Bxb3 16.axb3 Qd2

[+0.31] d=29 1...h6 2.Bxf6 Qxf6 3.d6 Bf5 4.h3 b5 5.Rd2 b4 6.Nb5 Rfd8 7.Nc7 Rab8 8.g4 Be6 9.Nxe6 Qxe6 10.Bc4 Qf6 11.Qxe4 Rxd6 12.Rxd6 Qxd6 13.Rd1 Qf6 14.Rd2 Rf8 15.h4 a5 16.Kd1 a4

[+0.36] d=27 1...Re8 2.Bc4 Bd7 3.d6 Rad8 4.Rd2 Bc6 5.Rhd1 h6 6.Bxf6 Bxf6 7.Nd5 Bxd5 8.Rxd5 Kg7 9.Qb3 Qxb3 10.Bxb3 b6 11.Bc4 Be5 12.R5d2 f5

[+0.37] d=26 1...c4 2.h4 Ng4 3.Bxg4 Bxg4 4.Rd2 Qd6 5.h5 gxh5 6.Nxe4 Qg6 7.Be7 Bf5 8.f3 Rfc8 9.Rdd1 c3 10.b3 Bh6 11.Kb1 Bxe3 12.d6 Bd2 13.d7 Rd8 14.Bxd8 Rxd8

(note 1) 2...Nxh2? 3.Rh1 Ng4 4.d6 Be6 5.Bxg4 Bxg4 6.Nd5 Bxd1 7.Rxd1 Qa5 8.Nf6+ Bxf6 9.Bxf6 c4 (9...Qxa2 10.Qxe4 Qa1+ 11.Kc2 Qa5 12.d7 is good for white) 10.Qxe4 c3 11.Bxc3 Rac8 12.d7 Rxc3+ is a mess favoring white

(note 2) 4...Bxa2?! 5.Nxa2 Nf3 needs a thorough refutation but 6.Bf6 Bxf6 7.Nc3, or even 5.d7! Nc6 6.f4 is good for white

(note 3) This line leads to an attack for black. White might instead investigate

a) 6.e4 [+0.00] d=29 6...Rc6 7.Be7 f5 8.f3 Rac8 9.h4 Qa5 10.Qa4 Nd3+ 11.Bxd3 Qxa4 12.Nxa4 cxd3+ 13.Nc3 Kf7 14.exf5 Bxf5 15.g4 Bxc3 16.gxf5 d2+ 17.Kb1 Bxb2 18.Kxb2 Rb6+ 19.Ka1 Rc2 20.fxg6+ hxg6 21.Rb1 Ra6, otherwise there is now

b) [+0.00] d=29 6.Be7 Qc5 7.e4 Nc6 8.f4 Nxe7 9.dxe7 Qxe7 10.f5 Bd7 11.f6 Bh6+ 12.Kb1 Qe8 13.h4 Rc5 14.Rd5 Rac8 15.h5 b5 16.hxg6 hxg6 17.Rh1 Bg5 18.Rxg5 Rxg5 19.Qd2 Rcc5 20.Bf3 Qe6 21.Ka1

(note 4)

a) 2.Bh4 [+0.00] d=26 2...Ne5 3.Qxe4 Bf5 4.Qf4 Rae8 5.f3 Bd7 6.d6 Re6 7.Rd2 Rxd6 8.Rhd1 Rxd2 9.Rxd2 Qe6 10.Nd5 f5 11.Be7 Re8 12.Bg5 Bc6 13.Nc7 Qxa2 14.Nxe8 Qa1+ 15.Kc2 Ba4+ 16.b3 Qa2+ 17.Kc1 Qa1+

b) +0.00/25 2.Bxg4 Bxg4 3.Rd2 Qa5 4.Be7 Rfe8 5.d6 b5 6.h4 h5 7.Rd5 Bxc3

c) +0.00/25 2.Rd2 Nxf2 3.Rf1 Nd3+ 4.Bxd3 exd3 5.Qxd3 Bd7 6.d6 c4 7.Qd5 Bc6

d) -0.23/25 2.Rdf1 Ne5 3.Bf4 Re8 4.h4 Nd3+ 5.Bxd3 exd3 6.Qxd3 Bf5 7.Qd2 Qa6 8.Re1 Bxc3 9.bxc3 Re4 10.Re2 Bd7 11.f3 Ra4 12.h5 g5 13.Bxg5 Bb5 14.Rf2 Bc4 15.Qe1 Bxa2 16.Rb2

e) 2.Nxe4 -0.28/29 2...Re8 3.f3 Bf5 4.d6 Nf2 5.Rhf1 Nxd1 6.Rxd1 h6 7.Be7 Rxe7 8.dxe7 Re8 9.Rd8 Rxd8 10.exd8Q+ Qxd8 11.Qxc5 a6 12.h3 Qh4 13.Qb4 Bxe4 14.Qxe4 Qe1+ 15.Bd1 Bxb2+ 16.Kxb2 Qxd1 17.a4 Qd7

(note 5) of course, 3.Qxe4 needs examination: after

a) [+0.14] d=30 3...c4 4.Qh4 h5 5.e4 (spot check: +0.03/26 5.e4) Bd7 6.d6 Nd3+ 7.Bxd3 Bxc3 8.bxc3 cxd3 and now [+0.03] d=26 9.Qf4 Qa5 10.Kb1 f5 11.e5 Be6 12.Rd2 and now +0.03/29 12...Rfc8 13.Qb4 Qxe5 14.f4 Qe4 15.Qd4 Qxd4 16.cxd4 Bd7 17.Re1 Rc6 18.Rxd3 Rb6+ 19.Ka1 Rxd6 20.d5 Re8 21.Re5 Bb5 22.Kb2 Kf7 23.Rde3 Rxe5 24.Rxe5 Bc4 25.Re7+

b) [+0.14] d=32 3...c4 4.Qh4 h5 5.d6 Bg4 6.f3 Be6 7.Bf6 Qxe3+ 8.Kb1 Bxf6 9.Qxf6 b5 10.Rfe1 Nd7 11.Qh4 Qb6 12.g4 hxg4 13.fxg4 b4 14.Nd5 Bxd5 15.Rxd5 Rac8 16.Bd1 Rce8 17.Re7 Qc6 18.Rd4 Qc5

(note 6) 4.Nxe4 [-0.13] d=23 4...Bf5 5.f3 c4 6.Kb1 Rac8 7.Bf6 Bxe4 8.fxe4 Bxf6 9.Rxf6 Kg7 10.Rff1 Qxe3 11.d7 Rcd8 12.Bxc4 Rxd7

Summary/Conclusion: all lines need deeper analysis to reveal the complete set of black's tactical opportunities.