Czech 65+ Open Championship Round Six

Spanton (1982) - Vladimír Dvořák (1912)

French 3.Nc3 Be7

1.Nc3 e6 2.d4 d5 3.e4 Be7!?

The position after 3...Be7!? occurs 1,247 times in ChessBase's 2025 Mega database. Among those who have played it are Nigel Short and Fabiano Caruana, while it was a favourite of Oleg Romanishin's in the 1970s.

How should White respond?

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4.e5!?

Most popular is 4.Nf3, but Stockfish17 prefers the text, while Dragon1 suggests 4.Bd3!?

4...c5 5.Qg4 Kf8!?

Dragon1 prefers 5...g6, but Stockfish17 fluctuates between the two moves.

6.Nf3 h5!?

There is only one example of this move in Mega25, but it is Stockfish17's top choice; Dragon1 prefers 6...b6.

7.Qf4 cxd4!?

The engines agree this is an improvement over the known 7...Nh6.

8.Nxd4

This is OK, but better is the engines' 8.Nb5! Nc6 9.Nbxd4.

8...g5!? 9.Qe3

The engines reckon 9.Qd2!? gives White a slight edge.

9...Nc6 10.Bd3 Nh6 11.h3 Kg7?!

The engines strongly dislike this, suggesting 11...Qc7 or 11...Nf5!?

How should White proceed?

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12.Bd2

The engines reckon 12.f4 gives the upper hand, and 12.Nce2 gives at least a slight edge.

12...f5!? 13.exf6+?!

Probably better is 13.f4. After the text Black's central pawns are free to advance.

13...Bxf6 14.Nce2?

Not 14.Nxe6+?? Bxe6 15.Qxe6? Re8 etc, but better is 14.Nxc6, although after 14...bxc6 Black's central dominance provides protection for the black king. Dragon1 reckons the resulting position is completely equal, but Stockfish17 marginally prefers Black.

14...Nxd4 15.Nxd4 e5!?

Black's hanging pawns are mobile and strong.

16.Nb3 e4 17.Be2 Nf5 18.Qc5 Be6

Probably even stronger is 18...Bxb2 19.Rd1 Bf6 20.0-0 Be6.

19.Bc3?

Better is 19.c3.

How should Black continue?

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19...Qc8?!

This largely lets White off the hook, whereas there is no good answer to 19...Rc8!, eg 20.Bxf6+ Qxf6 21.Qxa7 Rxc2! 22.Qxb7+ Bf7, after which Black is temporarily a pawn down, but has a very strong attack. Possibly better is 20.Qb4!?, but 20...Bxc3+ 21.bxc3 Qf6! is good for Black.

20.Bxf6+ Kxf6 21.Qxc8?!

There was no need to help Black develop the queen's rook.

21...Raxc8 22.0-0-0 Ke5 23.c3

Now 23...Rac8 leaves Black at least slightly better, according to the engines, but VD played ...

23...Bf7

... and offered a draw.

24.Nd4 Nxd4 25.Rxd4 h4!? 26.Re1 Bg6 27.f3 Rhf8 28.Bd3 Rf4

White has what looks like immense pressure against the hanging pawns, but it turns out there is no way to exploit this

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29.Bc2 Rc4 30.Rxc4 dxc4 31.a4 a5

White to play and lose

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32.b3?

White should 'do nothing', the position remaining completely equal

32...cxb3 33.Bxb3 Kf6!

There is no defence

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34.Bd5

This (and 34.Bd1, which comes to the same thing) is best, according to the engines.

34...exf3 35.Bxf3 Rxa4 36.Bxb7?

Restoring material equality, but making the win simple. Better is keeping rooks on with 36.Kb2, but 36...b5 leaves Black up the equivalent of a minor piece, or maybe more, according to the engines.

36...Ra1+ 37.Kd2 Rxe1 38.Kxe1 Ke5

Other moves also win, including 38...a4.

39.Kf2

Or 39.Bc6 Be4.

39...a4 40.Ba6 Bf7 41.Bd3 a3 42.Bb1 Kf4 0-1

Czech 65+ Open Championship Round Four

FACED an international master on board two.

Spanton (1982) - Milan Babula (2086)

French Exchange

1.e4 e6 2.d4 d5 3.exd5 exd5 4.Nf3 Bd6 5.c4 Nf6!?

More popular is 5...c6, but there are 1,482 examples of the text in ChessBase's 2025 Mega database.

6.c5!?

Much more popular is 6.Nc3, but Dragon1 marginally prefers the text, while Stockfish17 fluctuates between the two moves.

6...Be7 7.Nc3 0-0 8.Bd3 b6

This is the prescribed response to White pushing on with the c pawn in the manner of this game, and in this case the move scores a fabulous 71% in Mega25, albeit from 36 games.

9.cxb6 axb6 10.0-0

Now both sides have castled, how would you assess the position?

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Thanks to having an isolated queen's pawn, White has an extra pawn island, but the isolani is not much of a weakness. Both sides have a half-open file, but it may be easier for White to exert pressure on the c file than it is for Black to do likewise on the a file. The engines reckon the game is equal.

10...Ba6!? 11.Bf4 c5!? 12.Bxb8!?

The engines dislike this. Dragon1 suggests 12.Ne5 or 12.Bxa6, in each case claiming a slight edge for White; Stockfish17 reckons 12.Bxa6 is equal, but 12.a3 may give a slight edge.

12...Bxd3 13.Qxd3 Rxb8 14.b3 Rc8 15.dxc5!? bxc5 16.Rfd1 d4!? 17.Ne4 Nd5 18.Rac1

The engines suggest 18.Qc4!?

18...f5!? 19.Ng3

19.Ned2!? allows 19....Nc3 with a double-threat to d1 and a2. However the position is not altogether clear, one line running 20.Re1 Nxa2 21.Ra1 Nb4 22.Qc4+ Kh8 23.Ne5 Bf6!? 24.Nf7+ Rxf7 25.Qxf7 Nc2 26.Qe6 Nxe1 27.Rxe1, when the engines reckon White's activity gives decent compensation for a pawn.

19...g6 20.Ne5?!

Almost certainly better is 20.Ne2, with equality, according to the engines.

20...Bf6 21.Nc4?

This loses a pawn. Better is retreating back to f3.

21...Nc3 22.Re1

Not 22.Rd2? Bg5.

22...Nxa2 23.Ra1 Nb4

Materially Black is up a protected passed pawn, but is the equivalent of almost a minor piece ahead, according to the engines

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24.Qf3?? Nc2 25.Ra7 Nxe1 26.Qb7 Be7!? 27.Ne5!?

After 27.Qxe7 Qxe7 28.Rxe7 Rfe8 Black is up the exchange and a passer.

27...Rc7!? 28.Qxc7 Qxc7 29.Rxc7 Bd6 0-1

League Chess

PLAYED on board four (of eight) for Battersea against Streatham & Brixton 2 in London League Division Two last night.

Qixuan Han (2004) - Spanton (1985)

Réti

1.Nf3 d5 2.e3!? Nf6 3.c4 e6 4.Nc3 a6!? 5.b3 dxc4!?

This has been played by Hikaru Nakamura, but the main line in ChessBase's 2025 Mega database runs 5...c5 6.cxd5 (6.Bb2 is also popular) exd5 7.d4 Nc6, with what Stockfish17 and Dragon1 reckon is an equal position.

6.bxc4 c5 7.d4 cxd4 8.exd4

White has hanging pawns, which, as is fairly well-known, give space and cover a lot of important squares, but need piece-support

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8...Bb4 9.Qb3!?

This appears to be a novelty, and is the top choice of the engines. Known moves are 9.Bd2 and 9.Qc2.

9...Qe7?

This removes pressure from the key feature of the position, the hanging pawns. Correct is 9...Nc6, when the engines continue 10.Be2!? Ne4 11.Bb2 Qa5 12.Rc1 e5!? 13.0-0 (13.dxe5 Nc5!?) Bxc3 14.Rxc3!? exd4!? 15.Rcc1 Nc5 16.Qc2 Ne6, with what they reckon is a position with equal chances.

10.Be2 Ne4 11.Bb2 Bxc3+ 12.Bxc3 Nxc3 13.Qxc3 0-0 14.0-0

Now both sides have castled, how would you assess the position?

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White has a lead in development, as well as more space, and the hanging pawns are not under any pressure. However exchanges have eased the cramp in Black's position. The engines give White at least a slight edge.

14...Rd8 15.Rfd1 Nd7 16.Rab1

The engines suggest 16.c5!? Nf6 17.Qb3 Nd5 18.Ne5, claiming the upper hand for White.

How should Black proceed?

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16...Nf6?

The engines suggest a positional pawn sacrifice: 16...b5!? 17.cxb5 axb5 18.Bxb5 Bb7!? (18...Rxa2 19.Qc7) 19.a4 Rdc8, although they give White at least a slight edge.

17.Ne5 Qc7

Not 17...Rb8? 19.Nc6!

18.Bf3 Rb8 19.Qb4!

A clever move that takes advantage of the fact Black has nothing better than ...

19...Bd7

... which allows the white queen to enter Black's position.

20.Qe7 Rf8 21.Bh5?!

The engines much prefer 21.c5!? or 21.g4!?

21...Nxh5 22.Qxd7

Maybe a tad better is 22.Nxd7!? Kh8 (only move) 23.d5, with an initiative.

22...Rfc8 23.Qxc7 Rxc7 24.d5 exd5 25.cxd5 Nf6?

Equalising is 25...Rd8.

26.d6 Rc5

Also losing is 26...Rc8 27.Rd8 Nc6!

27.f4 b5 28.Rbc1 Ne4

Or 28...Rxc1 29.Rxc1 Rd8 30.d7! Nxd7 31.Nxd7, when the threat of back-rank mate prevents ...Rxd7.

29.d7 Rd8 30.Rxc5 Nxc5 31.Rc1 Nb7

Or 31...Nxd7 32.Nxd7, and again ...Rxd7 loses to back-rank mate.

32.Rc8 f6 33.Nc6 Rf8 34.Rc7 Nd8 35.Nxd8 1-0

Streatham & Brixton won the match 5-3.
MY BATTERSEA SEASON 2024-5

DATE.....EVENT...........................COL..RATING..OPP'S RATING..SCORE..SEASON PERF

12/9/24..Central London League....W......1933..........1886................1............2286

26/9/24..Central London League....B.......1933..........2112................1............2399

15/10/24.Club Championship.........W......1968..........1578................1............2259*

31/10/24.Central London League...B.......1968..........1867................0...........2061*

19/11/24.London League...............W.......1957..........1991................1............2127*

21/11/24.Central London League...B.......1957..........2035................=............2112*

27/11/24.London League...............W.......1957..........1723................=............2056*

12/12/24.Central London League...B.......1965..........2153................0............2018*

7/1/25.....Club Championship.........B.......1958..........1785................1............2037*

9/1/25.....Central London League...B.......1958..........1851................0............1978

14/1/25....Eastman Cup.................B........1958..........2052................1............2021*

28/1/25....London League..............B........1958..........1766................1............2033*

4/2/25......London League..............B........1980..........1757................1............2043*

6/2/25......Central London League..W.......1980..........1932................0............2006*

11/2/25....Central London League..B........1986..........2178................=............2018*

13/2/25....Central London League.W........1986..........1998................1............2042*

27/2/25....Central London League..B........1986..........1996................0............2015*

13/3/25....Central London League..B........1984..........2286................0............2008*

17/3/25....London League..............W........1984..........1870................0............1980*

3/4/25......Central London League..W.......1985...........2127...............0............1967

8/4/25......London League..............W........1985..........1992................=............1968

9/4/25......London League...............B........1985..........2004................0............1952

*My season's performance is slightly better than this as my win against a 1578 was a 1978 performance, lowering my average despite me winning.

I also scored a default win in a Croydon & District League match.

Cap Negret Round Seven

Alicante's tram system runs through Altea on its way to the mountains

FACED my third Spaniard on the trot.

Pascual Villa Caigüelas (1570) - Spanton (1808)

QGD 4...c5

1.d4 d5 2.c4 e6 3.Nc3 Nf6 4.Bg5 c5 5.cxd5 cxd4 6.Qxd4 Be7 7.e3!?

7.e4 is the main move, at least in ChessBase's 2023 Mega database, but the text scores four percentage points better at 59%.

7...exd5 8.Nf3 0-0 9.Be2 Nc6 10.Qd2 h6!?

Provocative. It was played by Jonny Hector (2465) in a 1990 Spanish championship game, but normal is 10...Be6.

How should White respond?

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11.Bh4!?

After 11.Bxf6 Bxf6 12.Nxd5 (12.Qxd5?? Bxc3+ etc) Bxb2 13.Qxb2 Qxd5, the game is equal, according to Stockfish16, but Komodo14.1 gives White a tiny edge.
11...Be6 12.0-0 Ne4!?

This is a thematic move in IQP positions in which White has not fianchettoed the king's bishop.

13.Nxe4 Bxh4 14.Nc5 Be7 15.Nb3

Not 15.Nxb7?? as 15...Qb6 traps the knight.

15...Qb6 16.Nfd4!?

The engines like this somewhat counter-intuitive move.

16...Bb4 17.Qd1 a5 18.a3 Bd6 19.Nxc6?!

There is a general rule in IQP positions that the player fighting the isolani should be particularly happy at swopping off knights, but here 19.Nxe6 is probably better.

19...bxc6 20.Qc2 c5 21.a4!? Rfd8 22.Rfd1 Rac8 23.Bb5 g6 24.Qd2

Black to play and win (well, get a positionally winning advantage, according to the engines)

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24...Bc7?

Black has several better moves, but perhaps the most surprising, at least at first sight, is 24...d4!? The point is 25.Nxa5 runs into 25...dxe3, when 26.fxe3 loses to 26...Bxh2+ etc.

25.Rac1 Bd7?

Black still has a slight edge, according to the engines, after 25...Bd6!?

26.Rac5 Bxh2+ 27.Kxh2 Rxc5 28.Nxc5 Bxb5 29.axb5 Qxc5 30.Qxa5 Rb8 31.b4 Qxb5 32.Qxb5 Rxb5 33.Rd4 f5 34.Kg3 Kf7 35.Kf4 Ke6

This rook-and-pawn ending is completely equal, according to the engines

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36.g4!?

An interesting decision as Black now gets a protectable passed pawn, but the position remains completely equal, according to the engines.

36...fxg4 37.Kxg4 Rb7 38.f4 Rc7 39.e4 dxe4 40.Rxe4+ Kf6 41.b5 Rc3 42.Rb4 h5+ 43.Kh4 Kf5?

Black holds the draw with 43...Rc7.

44.b6 Rc8 45.b7 Rb8 46.Kg3 Ke6

White to play and win

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47.Kh4

This does not spoil anything, but the correct plan starts with 47.Rb6+, eg 47...Kf5 48.Kf3 leaves Black in zugzwang, but 47...Kd5 48.Kh4 Ke5 49.Kg5 Kf3 50.Rb4 Kg3 51.Rb3+ Kg2 52.Kh4  Kf2 53.f5! gxf5 54.Kxh5 f4 55.Kg4 also wins for White.

47...Kf5 48.Kg3 ½–½

Delayed Sicilian Wing Gambit

PLAYED last night in the Battersea Club Championship at the club's home venue, Battersea Labour Club.

Spanton (2041 ECF) - Tim Valentine (1753 ECF)

Sicilian ...e6

1.e4 c5 2.Nf3 e6 3.g3 Nc6 4.Bg2 Nf6 5.e5!?

It is much more normal to defend the e4 pawn by 5.Qe2, 5.d3 or 5.Nc3, but in playing the text I had a gambit idea in mind.

5...Ng4 6.b4!?

Offering Black the choice of two pawns. There is just one game with this move in ChessBase's 2022 Mega database.

How should Black respond?

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6...Ngxe5

Attila Czebe (2465) - Jakub Szotkowski (2369), Budapest GM Tournament 2017, saw 6...Qc7!? 7.bxc5 Bxc5 8.0-0 Ngxe5 9.Nxe5 Qxe5 10.c3 with an unclear position (the game is listed in Mega22 as a win for White in 31 moves - perhaps on time as the final position is only slightly better for White, according to Stockfish14.1 and Komodo12.1.1).

An obvious alternative is 6...Nxb4, when the engines continue 7.0-0 Nc6, which also seems unclear but which they reckon slightly favours Black.

Another possibility is 6...cxb4, eg 7.d4 d6 8.h3 Nh6 9.0-0, when again the question is whether White has quite enough compensation for a pawn.

7.Nxe5 Nxe5 8.bxc5 d5

Not 8...Bxc5?? 9.d4.

9.cxd6

9.d4!? seems a viable alternative.

9...Bxd6 10.0-0 0-0 11.d4 Nd7!?

This may be a tad slow, but 11...Nc6 and 11...Nc4 are not all plain-sailing either.

12.c4 Nf6 13.Bb2

The engines prefer the arguably more-aggressive 13.Nc3 and 13.c5!?

13...Qc7 14.Qe2 Bd7 15.Rd1 Rfe8 16.Nd2 Bc6 17.Nf3

Avoiding an exchange of light-square bishops, but the engines reckon 17.Rac1!? Bxg2 18.Kxg2 Qc6+ 19.Qf3!? Qxf3+ 20.Kxf3 favours, if anyone, White.

17...Rac8 18.Rac1 Qa5 19.a3 Qh5 20.Re1 Ng4 21.h3 Nf6 22.Qd3 Nd7

How should White proceed?

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23.g4!?

Double-edged, but Black is not well-placed to exploit white kingside weaknesses. The engines are OK with the move, but prefer something like 23.Re3 or 23.Bc3!?

23...Qa5

On 23...Qg6 I intended 24.Qd2, when the engines reckon 24...Bxf3!? is the only way to maintain equality.

24.Bc3!

Forcing the black queen off the rank.

Black has to find an only-move

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24...Qd8
Not 24...Qa6 or 24...Qa4 as both moves are met by 25.Ng5 or 25.d5, in each case with a large advantage for White, while 24...Qxa3 is also calamitous after 25.Ng5 or 25.Ra1.

The engines give best-play as 24...Qc7! 25.d5 Nc5 26.Qb1, when 26...exd5 27.cxd5 Bxd5 28.Ng5 Bh2+ 29.Kh1 Bxg2+ 30.Kxg2 g6 31.Rxe8+ Rxe8 32.Qb5 gives White full compensation, but no more, for a pawn, according to the engines.

25.d5 Nc5

Or 25...exd5 26.Rxe8+ Qxe8 27.Ng5 Nf8 28.Qd4 Be5 (an amusing sideline runs 28...f6 29.Bxd5+ Bxd5 30.Qxd5+ Kh8 31.Nf7+ Kg8 32.Nh6+ Kh8 33.Qg8#) 29.Qxe5 Qxe5 30.Bxe5 f6 31.cxd5 Bd7 32.Rxc8 Bxc8 33.Bxf6 gxf6 34.Ne4, when White is only a pawn up but has an overwhelming position. If 27...g6, White has 28.Re1, eg 28...Ne5 29.Qd4 f6 30.f4 etc.

26.Qd4 e5 27.Nxe5 Rxe5

27...Bxe5 comes to the same thing, while 27...Nb3 28.Nxf7 Nxd4 29.Nxd8 Ne2+ 30.Rxe2 Rxe2 31.dxc6 Rxd8 32.cxb7 gives White three pawns and much the better position for an exchange.

28.Rxe5 Bxe5 29.Qxe5 f6 30.Qe3 Bd7

White is a pawn up but also has powerful bishops and a dangerous protected passed pawn 

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31.Bd4 b6 32.Re1 Nb7 33.Bf1 Qc7 34.Qd3 b5?

It is hard to explain this.

The game finished:

35.cxb5 Nd6 36.Re7 Qd8 37.Bxf6! Bxb5 38.Rxg7+ Kf8 39.Qxh7 1-0

Garry Kasparov's Forgotten Weapon Against The Queen's Gambit (part five)

IN the same tournament in which Kasparov beat Yasser Seirawan he faced Bent Larsen.

Larsen (2555) - Kasparov (2690)

Nikšić (Yugoslavia) Round 7 1983

1.c4 e6

Kasparov angles for another opportunity to play the Tarrasch Defence.

2.Nc3

Larsen indicates he is happy to oblige. He could have avoided the Queen's Gambit with, for example, 2.Nf3, when 2...d5 3.g3 c5 could be classified as a Réti or as a Symmetrical English.

2...d5 3.d4 c5 4.cxd5 exd5 5.Nf3 Nc6 6.g3 Nf6 7.Bg2 Be7 8.0-0 0-0 9.b3!?

This move goes back to at least 1920 but is dubbed the Uhlmann Variation in Play The Tarrasch by Shamkovich & Schilller (Pergamon (1984). As is pointed out in the book, the position can arise from a Nimzowitsch-Larsen Opening, ie 1.b3.

9...Ne4!?

This is the main move in ChessBase's 2021 Mega database, and is called "very sharp" by Shamkowich & Schiller.

10.Bb2 Bf6 11.Na4

A reasonably popular alternative is 11.e3, when 11...Bg4 12.h3 (12.Ne2 is the main move, but the engines slightly prefer the text) cxd4?! (Black should probably capture on f3 or withdraw the dark-square bishop) 13.Nxd5! was better for White in Spanton (1968) - John G Cooper (Hull - 2193), Hull 2017 (but ½–½, 53 moves).

11...Re8!?

More popular, but not by much, is 11...b6 (note that after 11.Na4, White is not threatening 12.Nxc5?? as that loses to 12...Nxc5 13.bxc5 Bxb2, but White is threatening 11.dxc5).

12.Rc1

12.dxc5 does not even come close to winning a pawn as Black replies 12...Bxb2 13.Nxb2 Nc3 etc.

12...b6!?

This had been played before but largely slipped under the radar because of Spassky's 12...cxd4 13.Nxd4 Bxd4 14.Nxd4 Bf5, when White has the bishop-pair and a slight edge, according to my main analysis engines Stockfish12 and Komodo11.01, but Black's position looks solid enough.

Today the text is the main move.

13.dxc5 Bxb2 14.Nxb2 bxc5 15.Na4

Black's hanging pawns come under immediate pressure.

15...Ba6

Active defence. Black's position looks problematic after 15...Nb4?! 16.a3 Na6, while the pawn sacrifice 15...c4?! 16.bxc4 d4 did not work out in Attila Jakab (2367) - Nathaniel Graham (2346), Budapest IM-A 2002, after 17.Nd2 Bf5 18.Nxe4 Bxe4 19.Bxe4 Rxe4 (1-0, 60 moves).

16.Re1

Not 16.Nxc5? Nxc5 17.Rxc5 Bxe2 etc.

16...c4 17.Nh4?!

This move has not find favour with later players. Today the main line runs 17.Nd2 Qf6 18.Nxe4 dxe4 19.bxc4 Rad8 20.Qb3 e3!, when Black has full compensation for a pawn, according to the engines, eg 21.fxe3 Qh6 24.Nc5 Rxe3 25.Qb2 Ne5, which led to a quick draw in a 'freestyle', ie computer-assisted, rapid game in 2006.

17...Qa5 18.Nf5 g6 19.Nd4 Rac8 20.h4?!

The engines dislike this, reckoning White keeps the balance with 20.Bh3 f5 (20...Rc7? 21.Nxc6 Rxc6 22.Bd7) 21.Nxc6 Rxc6 22.Bg2.

20...Ne5 21.Bh3 Rc7 22.Nc2?

This allows a combination. The engines prefer 22.Kg3, albeit reckoning Black is on top.

22...cxb3

Even stronger is the engines' 22...Nd3! 23.exd3 cxd3 24.Re3 (24.Ne3 Rxc1 25.Qxc1 d2) dxc2, when 25.Rxc2? only makes matters worse after 25...d4 26.Re1 Rxc2 etc.

23.axb3 Bc8 24.Bg2 Ng4 25.Rf1 Bd7?!

And here almost certainly stronger is 25...Ba6, eg 26.Nd4 Rec8, eg 27.Rxc7 Qxc7 28.Bxe4 dxe4, when the threat of ...e3 is extraordinarily hard to meet.

26.Ra1 Bxa4 27.Rxa4 Qc3 28.Bxe4

Forced, but good.

28...dxe4 29.e3?!

White should have protected the b pawn, for example by 29.Na3, according to the engines.

29...Qxb3 30.Rxe4 Rxe4 31.Qd8+ Kg7 32.Qxc7 Rxc4 33.Nd4 Rxc7 34.Nxb3 Rc2

Larsen correctly calculated that 29.e3?! did not lose material, but the ending favours Black thanks to his farside passed pawn and more-active pieces.

35.Nd4 Ra2 36.e4 Rd2?!

Black should have got on with it on the queenside with 36...a5, according to the engines, who reckon the text allows White to equalise.

37.Nc6 a6 38.e5

Stockfish12 is happy with this, but Komodo11.01 does not like it. Perhaps a surer draw is to be had with 28.f3!?, eg 38...Ne3 39.Re1.

38...Re2 39.Ra1 Rxf2 40.Rxa6 Rc2 41.h5 Kh6

Black is a pawn up but with almost zero winning chances after 41...gxh5?!

42.hxg6 hxg6 43.Ra4 Kg5 44.Nd4 Rc3 45.e6 Rxg3+ 46.Kh1!?

Kasparov gave this a question mark, but it seems that the losing move comes later.

46...f5 47.e7 Re3 48.Nc6 f4 49.Ra5+!?

Kasparov also gave this a question mark, but again that may not be right.

49...Kh4 50.Ra8 Nf6

White to play and draw

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51.Kg2?

This is the losing move, according to the engines.

I will explain later why they reckon 51.Kh2 is correct, but for now here is how the game ended:

51...f3+ 52.Kf1

52.Kf2 Ng4.

52...Kg3 53.Nd4 Ng4 54.Nxf3 Rxf3+ 55.Kg1 Nh2 56.Rf8 Rc3 0-1

Going back to the last diagram, White seems to draw with 51.Kh2, after which ...f3 does not come with check. The engines reckon 51...f3 is still best, but then comes 52.e8=Q! Nxe8 53.Ra4+ Kh5 54.Kg3, after which there seems no way for Black to save the f pawn, and then White should be able to give up his knight for the other pawn and reach a reasonably easy-to-draw ending, at least for a player of Larsen's calibre, of rook versus rook and knight. Best play seems to go 54...g5 55.Nd4 Re6 (55.Rc3 Ne5) 56.Nd4 Rf6 57.Nxf3! g4 58.Ra5+ Kh6 59.Ra3 gxf3 60.Rxf3 - Draw.