Showing posts with label Trompowsky. Show all posts
Showing posts with label Trompowsky. Show all posts

Wednesday, 7 April 2021

Beat The ... Trompowsky

IN this series I am looking at the statistically best way to play against popular opening lines.
The numbers are drawn from the 2021 edition of ChessBase's Mega database, ignoring, where possible, those results that include very few games and so are statistically insignificant.

The Trompowsky: 1.d4 Nf6 2.Bg5 goes through surges of popularity, often based on the publication of a dedicated book or repertoire recommendation.
Black's most-popular reply is 2...Ne4, which scores a respectable 46%.
But the most-successful move is Nakamura's favourite, 2...c5, which scores an excellent 50%.
Position after 2...c5
White has four main tries.

A) 3.Bxf6 (3,430 games)
The thematic move of the Trompowsky, but it only scores 49%, so Black already has an edge, statistically speaking.
Capturing towards the centre with 3...gxf6 is normal, at which point White usually pushes on with 4.d5 and Black replies 4...Qb6.
White could defend with 5.b3, but scores just 38%, so the main move is the ugly-looking 5.Qc1.
Black has a big choice here, but the most successful of the statistically significant ones is 5...d6, scoring 51%.
This is about as far as we can get with reasonable sample sizes. The position is rated as equal by the analysis engines Stockfish13 and Komodo12.1.1.

B) 3.d5 (2,411 games)
White grabs space, but gives Black a second chance to avoid the thematic capture on f6, and this, from a statistical view, is what Black should do by playing 3...Ne4, which scores 51%.
White usually replies 4.Bf4 (the other natural-looking retreat, 4.Bh4, scores an abysmal 15%, albeit from a small sample), when again it is time for 4...Qb6.
White has three popular continuations.
B1 5.Bc1, when 5...e6 6.f3 Nf6 7.e4 scores 51% for Black, while Kasparov's choice of 7.c4 is slightly less popular and scores 53% for Black.
B2 5.Nd2!? Qxb2 6.Nxe4 Qb4+ 7.Qd2 Qxe4 scores 54% for Black.
B3 5.Qc1 again looks ugly and is well-met by 5...c4 6.e3 Qa5+ 7.Nd2 c3! 8.bxc3 Nxc3, which scores 59% for Black.

C) 3.Nc3 (845 games)
This simple developing move is best met statistically by 3...d5, which scores 49%.
White has two main replies.
C1 4.Bxf6 gxf6, when this line splits:
C1.1 5.e3, after which Black scores 59% with 5...Nc6, rising to 61% after 6.Qh5 cxd4 7.exd4 e6.
C1.2 5.e4!?, after which Black scores 57% with 5...exd4, rising to 65% after 6.dxc5 f5 7.Qxd8+ Kxd8 8.0-0-0+ Bd7.
C2 4.e3. when 4...cxd4 scores a tremendous 72%, rising to 81% after 5.exd4 Nc6 and to 77% after 5.Qxd4 Nc6.

D) 3.dxc5 (304 games)
Black scores 58% with the unusual 3...Na6!?
The main line runs 4.Nc3 Nxc5 5.Bxf6 gxf6, after which Black scores a still very good 55%.

Friday, 14 August 2020

Summer Prague Round Eight

FACED a German this afternoon in round eight of Summer Prague U2000.
Lukas Hochscheidt (1754) - Spanton (1831)
Veresov
1.d4 d5 2.Bg5
The game starts as a Pseudo-Trompowsky ...
2...Nf6
... quickly turns into a regular Trompowsky ...
3.Nc3
... and finally becomes a Veresov.
3...Nbd7 4.f3 h6 5.Bh4 e6
The main alternatives, 5...c5 and 5...c6, are preferred by the analysis engines Stockfish11 and Komodo11.01.
6.e4 Be7 7.Nh3?!
This runs into a tactical shot, which costs White a pawn for what seems insufficient compensation. The main line runs 7.e5 Ng8 8.Bf2, as first played in Tartakower - Yates, Carlsbad 1923, which was drawn in 40 moves.
7...Nxe4!?
This idea was missed, or at least not played, by a 2221 in the only game to reach this position in ChessBase's 2020 Mega database.
8.Bxe7 Nxc3 9.Bxd8 Nxd1 10.Bxc7 Nxb2 11.a4?!
The knight will not be trapped, and the white a pawn becomes a target for Black's pieces, so 11.Rb1 was probably better.
11...Nb6 12.Kd2?
LH explained after the game he missed that the a4 pawn can be captured. White had to play 12.a5, when after 12...N6c4 White has the bishop-pair and better coordination.
12...N2xa4 13.Bb5+ Bd7 14.Rhb1 Bxb5+ 15.Rxb5 Kd7
Not 15...Nc4+ 16.Kc1 Nab6?? as it loses a piece to 17.Bxb6 etc.
16.Bxb6 Nxb6 17.Kd3 Rhc8 18.Rba5 a6 19.Nf4 g6 20.Ne2 Rc6 21.Nc1 Rac8 22.R1a2 Rc3+ 23.Kd2 Nc4
The engines are not keen on this, but I felt exchanging a pair of rooks made it easier to mobilise Black's queenside pawns.
24.Kxc3 Nxa5+ 25.Kd3 b6 26.Ne2 Kc7 27.Nc3 Nc6 28.Rb2
28.Rxa6?? Nb4+.
28...b5 29.Rb1 Ra8 30.f4 h5 31.h3 Rb8 32.g3 Rb6?!
This lets White open and occupy a file on the kingside, after which Black is still winning but the danger of falling to a trick increases.
33.g4 hxg4 34.hxg4 Rb8 35.Rh1 Kb6 36.Rh7 Rb7
The engines prefer the passive 36...Rf8!? followed by pushing the queenside pawns.
37.f5 gxf5 38.gxf5 Rc7 39.Rh6 Nb4 40.Kd2 Rc6 41.Rh8 Ka5 42.Rf8 Nxc2! 43.Kxc2 b4 44.Rxf7 Rxc3+ 45.Kb2 exf5!?
Eliminating the dangerous f pawn seems best.
After ...
46.Rxf5 Ka4 47.Rxd5
... White is only one pawn down, but is completely lost.
47...Rc4 48.Rd8 b3 49.d5 Rc2+ 50.Kb1 a5 51.d6 Rd2 52.d7 Ka3 53.Kc1 Rd5
Also winning is 53...b2+ 54.Kxd2 b1=Q.
54.Ra8 b2+ 55.Kc2 Rc5+ 56.Kd2 b1=Q 57.d8=Q Qa2+ 58.Ke3 Qe6+ 0-1