Game of the Month

Long Diagonals

Most players are familiar with the amazing attacks that can occur when one player is working with a bishop on a long diagonal heading towards the other side's castled king. Some of the more artistic ideas involve knights leaping onto the diagonals and then off, creating havoc with discovered attacks. In the game between Georgi Kacheishvili and Judit Polgar from the penultimate round of the 1998 U.S. Open, a nightmarish tactical situation arose when both players set up potential long diagonal batteries zeroing in on the opposition's cornered king. The slugfest had started when Polgar made an instructive pawn sacrifice to obtain play on the light squares. When Kacheishvili was finally persuaded to abandon his blockade of Polgar's bishop in order to set up his own dark-squared battery, he was met by a brutal queen sacrifice, which reestablished that Polgar's diagonal was the one that counted.

US Open Hawaii, 1998 Round 8

Kacheishvili,G - Polgar,J [E94]

1.d4 Nf6 2.c4 g6 3.Nc3 Bg7 4.e4 d6 5.Be2 0-0 6.Nf3 e5 7.0-0 Na6

Another fairly popular new idea against 7 O-O is 7 ... Qe8, trying to

exert latent pressure against e4, but a good response to that is 8 dxe5

dxe5 9 b4!

8. Re1

Kacheisvili employs a direct and simple approach. 8 dxe5 would not be

effective as after 8 ... dxe5, an eventual capture with Nf3xe5 can always

10.Bf1 Ng4

Activating this knight is important, as it frees up the possibility of … f7-f5 later.

11.f3

DIAGRAM

Ne5

Robert Byrne points out that 11 ... Nxh2?? 12 Kxh2 Qh4+ 13 Kg1 Bd4+ 14 Qxd4 Qxe1 15 Bh6 wins for White.

12.Be3 Nc5 13.Qd2 Ne6

The position is unbalanced because Black's knights, while active, are unstable and might be pushed back. Thus, Kacheisvili chooses to avoid the offered exchange of knights, hoping to eventually extend his space advantage.

14.Nc2 Qh4 15.Rad1 f5

This move, while somewhat weakening to Black's kingside, accomplishes the twin objectives of breaking down the bulwark blocking the e-file, and removing the specter of White creating trouble with a later f3-f4-f5. With the e-file open, it is more likely that any tactical tricks that Black may have to rely on will work.

16.exf5 gxf5 17.b3 Kh8

This is stronger than 17 … f4 18 Bf2 Qg5 19 Kh1, when Black has no effective followup, and Nc3-e4 is looming.

18.Nd5 Rg8 19.Kh1 Bd7 20.f4

Kacheishvili finally gives the boot to the knight on e5. He waited until he had set up a completely harmonious defensive formation, as the knight gains access to other squares which can be dangerous, if only temporarily.

Ng4 21.Bg1 Rae8 22.g3 Qh5 23.Bg2

DIAGRAM

Kacheishvili is about to start harvesting the fruits of his positional advantages spearheaded by the knight outpost on d5.

Nc5!?

I think this shows great judgment in figuring that the comparative risk of the speculative pawn sacrifice entailed by this move is less than that suffered by remaining passive. or trying to find a way to boot the d5 knight out with ... c6 without causing d6 to become fatally weak.

24.Nxc7 Ne4 25.Bxe4

Of course this is forced due to the enormous pressure on f2 and g3.

Rxe4 26.Rxe4

A natural move because White will get a nice blockader on e3, while e4 can no longer be used for Black's pieces, and the long diagonal closes. However, the almost-as-dangerous diagonal c8-h3 opens, and the previously static f5 pawn is turned into a passer. I believe a better system of defense was 26 Nb4! Then the b4 knight travels to d5 to shut down the long diagonal, while its compatriot on c7 stops Black from douboling on the open file.

fxe4 27.Nd5?

Overlooking that Black's knight on g4 has been transformed into a desperado, Kacheishvili makes a serious error. Indicated was 27 Qe2, for example, hindering the organization of Black's attack.

Ne5!

Suddenly it becomes clear that if 28 fxe5? Qf3+ 29 Qg2 Qxd1 will decide. Thus, with tempo, the Black knight has scrambled its way into f3.

28.Bd4 Nf3

The players agreed after the game that 28 … Bg4 was the correct way to prosecute the attack. Then White should probably play 29 dxe5 (29 Rf1 Bf3+ 30 Kg1 Nd3 is a very strong attack for Black), and then after 29 … Bxd1, there is a choice of 30 exd6, 30 e6, and 30 Nf6. However, after 29 dxe5, Black has 29 … dxe5, which maintains the advantage after, for example, 30 Re1 exd4 31 Nxd4, as the two bishops vs. two knights outweighs the fact that White is a pawn up. , giving White the option of sacrificing the Exchange or allowing Black's minors to continue congregating in the area of his king.

29.Qe2

A very tricky situation, and horrendous to play in time pressure. He cannot play 29 Qf2 because of 29 … Nxh2. But after the text, Black gets nowhere with 29 … Bxd4 30 Nxd4 Rxg3 31 Nf6.

Bc6

DIAGRAM

The position is dynamically unclear. Black has some very well placed units in return for his pawn sacrifice, and White is facing a serious challenge as to how to defend the pawn on g3. However, this move actually constitutes the sacrifice of a second pawn.

30.Bxg7+

Not 30 Nf6 e3 and 31 Nxh5 would be destroyed by 31 … Nxd4+.

Rxg7 31.Nf6

Black would certainly stand better if she regained her pawn with either 31 Nce3 Rxg3, or 31 Rg1 Bxd5

Qf7

A mistake would be 31 … Qh6 32 Rxd6 Rxg3 33 Rd8+ Kg7 34 Rg8+ Kxf6 35 Rxg3.

32.Rxd6 Qe7

Polgar is still looking to cash in on that long diagonal, using tactics to stop White from fully blocking it.

33.Qd1

DIAGRAM

Very impressive-looking, as Kacheishvili not only defends the rook but also menaces 34 Rd8+. However, it turns out that the move does not actually give sufficient support to the d6 rook. Continuing complications would follow the correct 33 c5 e3 34 Nd5 Bxd5 35 Rxd5 Qe4 36 Rd8+ Rg8 37 Rxg8+ Kxg8 38 Qxe3 Qd5, and even three pawns down, Black has a balancing initiative, for example 39 Nb4 Qd1+ 40 Kg2 Nd2, etc.

Rg6 34.Qa1

Again, very impressive, and humorous, that White is now using a long diagonal – until one sees what follows. White's best chance here was the bizarre sacrifice 34 Rd8+ Kg7 35 Nh5+ Kh6 36 Ne3 Kxh5 37 f5 (better than 37 g4+ Rxg4).

Qxd6!!

Polgar simply gives up her queen for rook and knight, as White's position afterwards is wrecked.

35.Ne8+ Kg8 36.Nxd6 Rxd6

Now the threat of 37 … Rd2 is overwhelming.

37.Ne3 Rd2 38.Nf1 Rf2

None of White's pieces can really move here.

39.Qd1 Kf7

Stopping the check on d8.

40.Qb1

Kacheishvili fell on time on this, his 40^th move. Black ends up a piece ahead after 40 … Rxf1+ 41 Qxf1 e3 and White's best is 42 Qd1 Nd4+ (preserving the bishop rather than the knight after 42 … e2 43 Qxe2 Nd4+ 44 Qg2) 43 Kg1 e2 44 Qc1 Nf3+. Instead of 40 … Rxf1+, Robert Byrne points out a beautiful forced win starting with 40 … Ne1!! Then the variations are (A) 41 Kg1 Rg2+ 42 Kh1 Rb2! 43 Qxb2 e3+ 44 Kg1 Nf3+ 45 Kh1 (or 45 Kg2 Ng5+) Ng5+ 46 Qg2 (46 Kg1 Nh3 mate) e2, (B) 41 Qxe1 e3+ 42 Kg1 Rg2+ 43 Kh1 Rxg3 mate, or (C) 41 Ne3 Re2 and if 42 Nd5 Nf3 or 42 Qc1 Nf3 43 Nf1 e3 44 Qxe3 Ng5+ 45 Kg1 Nh3 mate.

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