(The annotations to the following game, by Mikhail Tal, appear in '64' (№ 23, 1971). The translation from the original Russian is by Douglas Griffin.)

Korchnoi - Geller 7h match-game, FIDE Candidates’ Quarter-final, Moscow, 26th May 1971

The 7th and 8th games of the Geller-Korchnoi match were fated to be the last. Undoubtedly, the nerves of the participants in this duel were stretched to the limit, but if Korchnoi on the whole did not change his playing 'script', then the Moscow was unusually passive.

1.d4 Nf6 2.c4 g6 3.g3 The system associated with the of the 's is very often employed by the Leningrad grandmaster.

3...c6 Offering to the opponent a to the Gruenfeld Defence (4.Bg2 d5).

4.d5 Declining the offer. If my memory does not betray me, such a variation was already encountered in one of the games between Korchnoi and Geller from the Candidates' tournament in Curaçao. (Translator’s note: Tal's memory was not at fault; the game Korchnoi-Geller, from the 1st round of the Candidates' tournament, had gone 4.d5 Bg7 5.Bg2 d6 6.Nc3 0–0 7.Nf3 e5 8.0–0 cxd5 9.cxd5 , etc.)

4...cxd5 5.cxd5 d6 6.Nc3 Bg7 7.Bg2 XIIIIIIIIY 8rsnlwqk+-tr0 7zpp+-zppvlp0 6-+-zp-snp+0 5+-+P+-+-0 4-+-+-+-+0 3+-sN-+-zP-0 2PzP-+PzPLzP0 1tR-vLQmK-sNR0 xabcdefghy

7...Qa5! An interesting move. Into White's plan comes play on the 's flank, associated with the possible transfer of the along the route g1–f3–d2–c4 (b3). Now 8.Nf3 is impossible on account of 8...Ne4 or 8...Nxd5. In preventing this threat, White posts the bishop at d2, thereby depriving the knight of this important square.

8.Bd2 (Translator’s note: Later, in the game Furman-Vasiukov (40th USSR Championship Semi-final, Uzhgorod 1972) White tried instead 8.e4 , but after 8...Bg4 9.f3 the continuation 9...Nxe4! would have been very strong.)

8...0–0 9.e3 Again there is not 9.Nf3 on account of 9...Nxd5.

9...Nbd7 10.Nge2 Ne5 XIIIIIIIIY 8r+l+-trk+0 7zpp+-zppvlp0 6-+-zp-snp+0 5wq-+Psn-+-0 4-+-+-+-+0 3+-sN-zP-zP-0 2PzP-vLNzPLzP0 1tR-+QmK-+R0 xabcdefghy

Black has played the opening succesfully, and his position is at any rate no worse.

11.0–0 Nc4 12.Bc1 Bg4 Black provokes the weakening advance f2–f3. Naturally, Korchnoi avoids this move.

13.Qb3 Rfc8 Escalating the pressure on the queen's flank. White naturally cannot continue 14.Qxb7? Rab8 15.Qxe7 Re8, and the queen is caught.

14.Nd4 Bd7 A struggle around the advance ...b7–b5 is underway.

15.Rd1 Rab8 16.h3 In order, in a series of cases, to cover the square g4.

16...a6 Having achieved an imposing position, Geller (as, incidentally, in the 8th game) does not act confidently enough. Deserving preference is the immediate 16...b5. Possibly Black feared the invasion of the knight at c6, but after 17.Nc6 Bxc6 18.dxc6 Qb6 Black has an excellent game.

17.a3 The beginning of an interesting plan, associated with the 'smoking out' of the c4–knight. One is left with the impression that this plan was not figured out by Black in time. Otherwise he would have necessarily have advanced his to b5.

17...Qc5 18.Qa2! Rc7 19.Nce2! This is Korchnoi's idea. White clears the path for the b-pawn. With the position of the knight at c3 its advance was impossible on account of the capture at e3.

19...Rbc8 Geller thought for rather a long time over this move. The black pieces, which were not so long ago actively placed, have become objects of attack.

20.b3 Ne5! Very passive would have been 20...Nb6 21.e4 , when it is very far from simple to unravel the tangle of black pieces on the queen's flank. XIIIIIIIIY 8-+r+-+k+0 7+ptrlzppvlp0 6p+-zp-snp+0 5+-wqPsn-+-0 4-+-sN-+-+0 3zPP+-zP-zPP0 2Q+-+NzPL+0 1tR-vLR+-mK-0 xabcdefghy

21.Bd2!? It is generally known that the Leningrad grandmaster reveres the acquisition of material. But on this occasion the win of a piece with 21.f4 proves not to be to his liking. Black would probably have continued 21...Qb6 , and if 22.fxe5 dxe5, then after a retreat by the knight the black bursts onto the 2nd rank. White, of course, is not obliged to take the knight immediately; he could continue, say, 22.Rb1, but in this case too the position remains very tense. Here is an approximate variation: 22...Nh5 23.fxe5 dxe5 24.Nf3 Rc2 25.Rb2 Rxc1!.

Therefore Korchnoi prefers the struggle with equal material.

21...Be8 The knight must all the same be saved. Again bad is 21...Nxd5 22.b4.

22.Rac1 Qb6 23.Rxc7 Rxc7 24.Bc3 The pawn at d5 noticeably restricts Black's activity. Experiencing a shortage of space, Black aims at exchanges.

24...Bb5 25.Qd2 Bxe2 26.Ba5! Qa7 27.Nxe2 Now White has the advantage of the two bishops - a factor which could become very important after the of the heavy pieces.

27...Rc8 28.Rc1 Qb8 29.Rc2 Possibly more accurate was 29.Rxc8+ Qxc8 30.Qc1. Here both players were experiencing a slight shortage of time.

29...Ned7 Exploiting the possibility of transferring the knight to a more active position.

30.Qc1 Rc5 31.Rxc5 Nxc5 32.Qc2 Qe8 33.Nd4 h5 A time-trouble oversight in a difficult position, which White (also on account of time trouble) fails to exploit. XIIIIIIIIY 8-+-+q+k+0 7+p+-zppvl-0 6p+-zp-snp+0 5vL-snP+-+p0 4-+-sN-+-+0 3zPP+-zP-zPP0 2-+Q+-zPL+0 1+-+-+-mK-0 xabcdefghy

34.Bb4 White forcibly achieved a decisive advantage, continuing 34.b4 . At Black's disposal there were three possibilities: 1) 34...Na4 35.Nc6 bxc6 36.Qxa4 with a decisive advantage for White. 2) 34...Qa4 35.bxc5 Qxa5 36.c6. 3) 34...Ncd7 35.Qc7 Qb8 (in the case of 35...Qa8 36.Nc6! is again decisive) 36.Qxb8+ Nxb8 37.Nc6!.

34...Qc8 35.a4 Qc7 36.a5 Serious attention was merited by 36.Ba3 and, in order to prevent the threatened b3–b4, Black would have been forced to continue 36...a5, weakening the b5–square (bad is 36...Qa5 37.b4! Qxa4 38.bxc5 Qxa3 39.c6).

36...Ne8 37.Ne2 Nd7 38.Qe4 Kf8 39.Qb1 Ne5 40.Bd2 Qc5 Time trouble is over, and the game was adjourned.

41.Nd4 Nd7 Very dangerous is 41...Nf6 on account of 42.f4 Ned7 43.Ne6+ fxe6 44.dxe6 Nb8 45.Qxg6 Kg8 46.g4 with an attack that can hardly be resisted. Also unfavourable for Black is 41...Nc7 42.b4 Qc4 43.Bf1! Qxd5 44.Qc2 with a dangerous assault on the queen's flank.

Possibly, the most peaceful of all was 41...Kg8. XIIIIIIIIY 8-+-+nmk-+0 7+p+nzppvl-0 6p+-zp-+p+0 5zP-wqP+-+p0 4-+-sN-+-+0 3+P+-zP-zPP0 2-+-vL-zPL+0 1+Q+-+-mK-0 xabcdefghy

(Translator’s note: - Regarding this game and the position after 41...Nd7 in particular, Korchnoi, in Chess is My Life (1977) writes: “In the 7th game Geller again turned to the King's Indian. He played the opening imaginatively and obtained an excellent game. In the middlegame I managed to neutralise the pressure on my position, and there was now a slight advantage on my side. The game was adjourned in a position which, 'according to the experts' was better for me. But, hard as I tried, I could find no real advantage. I attached great importance to the resumption of this game, and therefore the following day, for the first time in the history of matches for the World Championship, I asked for a postponement on the adjournment day! I prepared to play the 8th game the day after this, but now it was Geller who asked for a postponement. I don't know what he had in mind, but I devoted these days to a serious analysis of the adjourned position. There was no possibility of winning by quiet play. My second, Osnos, suggested an unexpected piece . It too did not give a win, but Black was forced to defend accurately, and White did not risk a great deal... he could still . I don't know what Geller did for those three days, but of course he hadn't analysed the piece sacrifice. At the board he failed to find the best defence, and in addition again ran short of time. I won.")

42.Ne6+!? As is well known, Geller very much dislikes to find himself under attack, and therefore the knight sacrifice (objectively speaking not the strongest continuation) was very unpleasant for him, the more so since in the analysis of the adjourned position he had seemingly spent insufficient time on this possibility.

42...fxe6 43.dxe6 Ne5! Much stronger than 43...Ndf6 44.Qxg6 Kg8 45.g4, and the position of the knight at f6 gives White an important for the advance of the g-pawn.

44.f4 XIIIIIIIIY 8-+-+nmk-+0 7+p+-zp-vl-0 6p+-zpP+p+0 5zP-wq-sn-+p0 4-+-+-zP-+0 3+P+-zP-zPP0 2-+-vL-+L+0 1+Q+-+-mK-0 xabcdefghy

Here Geller thought for a long time and took a clearly poor decision - to return the sacrificed piece to the opponent. Meanwhile, continuing 44...Nc6 45.Qxg6 Nd8 Black retained quite good defensive possibilities, since the approaches to his king are covered by both knights.

Possibly, in this case the best for White would have been the variation 45.Bxc6 Qxc6 46.Qxg6 Kg8 47.Qf7+ with a draw.

44...Nf6 45.b4! A useful intermediate move.

45...Qb5 46.fxe5 Qxe5 47.Qxg6 Qxe6 48.Bxb7 Qxh3 49.Qg5! Another possibility was 49.Bc3 with the threat of 50.Bd5.

49...Qe6 50.Bxa6 Qa2 51.Bc3 Qc2 52.Bxf6 Bxf6 53.Qh6+ Ke8 54.Qxh5+ Kd8 55.Qg4 Qb1+ 56.Kf2 In this hopeless position Black lost on time.