Czech Mate

FACED a Czech junior in the first round of the Summer Prague U2000 this afternoon.
Spanton (1831) - Pavlina Dudova (1496)
English Nimzowitsch
1.c4 e5 2.Nc3 Nf6 3.Nf3 Nc6 4.e4
Nimzowitsch poineered this set-up. Later it was refined into the Botvinnik formation in which White also puts pawns on c4 and e4 but places the king's knight on e2.

4...Bc5

This is the most popular reply in ChessBase's 2020 Mega database.

5.Nxe5

This well-known fork trick is often played by Black in similar positions in order to equalise, but here White hopes for more.

5...Nxe5

If 5...Bxf2+?! then 6.Kxf2 Nxe5 7.d4 (7...Neg4+ 8.Kg1) with h3 to come leaves White with the centre and the bishop-pair.

6.d4 Bd6?

This plausible-looking move has been played by grandmasters, but Nimzowitsch showed what is wrong with it against Réti at Berlin Tageblatt 1928.

How should White proceed?

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7.c5 Bxc5 8.dxe5 Ng8 9.Bc4!?

A simpler way to an advantage is 9.Qg4, as played by Nimzowitsch against Réti. That game continued 9...Kf8 10.Qg3 Ne7 11.Bc4 Ng6 12.f4 (1-0, 62 moves).

9...Ne7 

This is the choice of my main analysis engines Stockfish11 and Komodo11.01, but there is a major problem with Black's position.

10.Qg4

The engines give 10.b4!, the point being that after 10...Bxb4 11.Qb3 Bxc3+ 12.Qxc3 White is a pawn down but has more than enough compensation thanks to open lines for his bishops and heavy pieces. That leaves 10...Bb6, but White is clearly better.

10...Ng6

Also seemingly playable for Black is 10...0-0 (Black now threatens ...d5) 11.Qg3 (11.Bh6 Ng6 12.Bg5 Qe8 is good for Black) d6. The engines eventually give best-play as 10...d5!? 11.Qxg7 Rg8 12.Qxh7 dxc4 13.Nd5 with an unclear position.

11.Qg3

I felt 11.Bg5 Be7 12.Bxe7 Qxe7 simplified Black's task.

11...0-0

Komodo11.01 likes this but Stockfish11 prefers the retreat 11...Be7!?, although then both engines agree White is better after 12.Nd5.

12.h4 d6 13.h5 Nxe5 14.h6 g6?!

Good for Black is 14...Qf6? 15.Bg5? Bxf2+, but Black is busted after 15.Nd5 as 15...Bxf2+ 16.Qxf2 Qxf2+ 17.Kxf2 Nxc4 fails to 18.Ne7+ Kh8 19.hxg7+ Kxg7 20.Bh6+.

Best seems to be 14...Ng4 15.hxg7 Re8 (15...Bxf2+?! 16.Qxf2 Nxf2 17.gxf8Q+ Qxf8 18.Kxf2) 16.Qf3 Qf6 (16...Bxf2+ 17.Kf1) 17.Qxf6 Nxf6 18.f3, one point being that 18...Kxg7 19.Bh6+ gives White plenty of play for the pawn, according to the engines.

15.Bg5 Qd7?

Also bad is15...Bxf2+? 16.Kxf2 Ng4+ 17.Qxg4 Bxg4 18.Bxd8, but Black is still in the game after 15...Qe8 16.Nd5 Ng4 17.0-0-0.

16.Nd5 Ng4 17.Qxg4 Bb4+ 18.Kf1

The only winning move, but plenty good enough.

18...Qxg4!?

This speeds the end but the engines' 18...Qe6 19.Qf4 f6 20.Ne7+ is hopeless for Black.

19.Ne7+ Kh8 20.Bf6#