Chess 443

PHILIDOR

Specially contributed by R. W. Searley (Essex). White to play and mate in three moves; solution next week.

Solution to no. 442 (Sheppard): B - Kt 6, threat P - Q 4. 1 . P - B 4; 2 Q - Q 4. 1 . Kt-B 4; 2 Q-B 4.1 ...Kt-K 6; 2 Q-K4.

1 Kt (3) Kt 5; 2R - K 6. 1 ... Kt (2) - Kt 5; 2 R - B 5. Very fine example of unpinning by Black self-interference.

The world championship

A great struggle is taking place between the holder Tigran Petrosian and challenger Boris Spassky. At the time of writing the score is 104- Spassky's favour-5 wins, 3 losses and 11 draws. When one remembers how easily Spassky won all his matches en route to the challenge - 54-24 v. Geller, 54-24 v. Larsen and 64-31 v. Korchnoi - it is clear again what a great player Petrosian is, when he really exerts himself.

The course of the match has shown the fighting spirit of both players. Petrosian inflicted a severe practical and psychological blow on Spassky by winning the first game with Black in typical style, beating back Spassky's attack and winning the ending. Quite unaffected by this reverse Spassky won three of the next seven games drawing the others and I for one thought Petrosian was finished. Not so; winning two games in excellent style he levelled the match. Then after a series of hard-fought draws, Spassky won the seventeenth and nineteenth games to take the lead again.

Here is a Spassky win, with the players' times in minutes, move by move; they have 24 hours each for forty moves.

White, Spassky. Black, Petrosian. Opening, Queen's Gambit. (World Championship, game 5.) 1 P - Q B 4 0 Kt-KB 3 0 2 Kt-QB3 1 P - K 3 2 3 Kt - B 3 P - Q 4 3 4 P - Q 4 3 P - B 4 3 5 BP x P j Kt x P 6 P - K 4 1 Kt x Kt 7 P x Kt 0 PxP 1 8 PxP B - Kt 5 ch 2 9 B - Q 2 B x Bch 1 10 Q x B 1 0 - 0 Times to date; Spassky 8 minutes, Petrosian 134. This is a position that suits both players; White's chances lie in using his strong central position to build up a king's side attack, Black's in a superior ending if he weathers the storm.

11 B - B 4 Here Reshevsky (v. Horowitz) played B - Kt 5 to delay Kt - B 3. On B 4 bishop looks exposed but White has a farsighted idea in mind - see mom 15.

11 . . . Kt - B 3 5 Maybe II...P-Q Kt 3 is preferable (see move 15 also).

12 0 - 0 P - Q Kt 3 1 13 Q R - Q 1 1 B - Kt 2 5 14 KR-K1 I R - B 1 3

15 P - Q 5! 0 PxP 14

A critical moment. The natural 15 . . . Kt - R 4 is met by 16 P x P1, Kt x B; 17 P x P ch, K - R I (17 . . . K x P; 18 Q - Q 7 ch); 18Q x Q, Q R x Q; 19R x R,R x R; 20 P - K S with advantage to White. This may have been overlooked by Black on move 11.

16 B x P 3 Kt - R 4 19 17 Q - B 4 10 Q - B 2 6 18 Q - B 5! 8 Finely judged; White correctly estimates that his pawn on Q 5 will be a strength not a weak- ness. As the times indicate, we are now passing through the critical moves in the game.

18 ... B x B 20 19 P x B 2 Q - B 7 8 20 Q - B 4! 21 Q x P? 5 As Spassky shows, it is too dangerous to accept the pawn; Petrosian may, however, have thought that if he could not take it he would lose anyway - and may also have relied too much on his great defensive powers. Thnes: Spassky 57 minutes, Petrosian 994 - twenty move to go.

21 P - Q 6 6 Q R - Q 1 16 22 P - Q 7! 11 Q - B 5 2 23 Q - B 5 2 P - K R 3 7 Kt - Kt 5 was an unpleasant threat.

24 R-QBI 7 Q - R 3 3 25 R-B 7 22 P - Q Kt 4 4 Times: Spassky 105, Petrosian 1314 - so Petrosian has only 184 minutes for the next fifteen moves.

26 Kt - Q 4! 4 Q - Kt 3 4 27 R - B 8! 1 Kt - Kt 2 8 27...QxKt; 28R x R,R x R; 29 R-K8ch and wins or 27 . . .P- R 3 (to guard the Kt P); 28R-K8I,Qx Kt; 29R x Rch,R x R; 30RxRch,KxR;31 Q-B5c1d,QxQ; 32 P - Q 8 = Q mate. Note that Spassky took only five minutes over moves 26 and 27 - on move 25 he was no doubt working it out u detail.

28 Kt - B 6 5 Kt - Q 3 3 Petrosian now has 34 minutes for twelve moves but it no longer matters.

29 Kt x R 4 Kt x 30 Kt - B 6 0 Resigns.

White threatens 31 R x R ch, K x R; 32 R- K 8 mate and if 30 . . Kt - Q 3: then 31 R x R ch, K x R; 32 P- Q 8= Q ch with a rook ahead.