I play the Nimzo but not like this. Nimzovitch described it as an "ideal" Queen's Gambit, by which he meant that black would not actually occupy d5 & c5 with his pawns. In other words, a hypermodern opening.

So 5. ... c5, looks alien to me. But what are we to make of 7. e3 ...? The folks in Leningrad have peculiar tastes. After 10. ... 0-0, I prefer black.

The problem is 13. ... e4. Even though it stands for 30 moves, this pawn must obviously fall.

Play revolves around it for a few moves right away; it exerts a cramping influence. By 20. ... Ng7, the players have reached a temporary standoff and the action shifts to the Q-side with 21. b4 ....

Each side wishes to exchange under favorable conditions, which the other side keeps preventing, it is interesting. With 25. ... cxd5, the dust settles. We see the move f7-f5 will shore up the black K-side, and if he can ever play b7-b5 he will have good chances on the Q-side. White has a passed Q-pawn and two open files. What is the winning plan?

Boris chooses 26. d6 .... The discombobulating pawn adavance is the theme of this game. Nonetheless with 28. ... f5, black seems to be consolidating. White avoids 29. Nd5 ..., and plays 29. Nb5 ..., instead.

The threat is Nc7 with double attack on the disconnected enemy Rooks. Good eye, Boris. 29. ... Bxb5, weakens the black K-side by removing a protector, so a Rook moves instead. After 31. ... Bxc7, white's pawn would be even more annoying, so now the other Rook moves.

Finally after 32. Nd5 ..., the Knight comes home where it belongs. With 33. Qb2 ..., it is white who has triumphed. Black has played f7-f5 but it is shaky on the open file; the other open file is occupied by the Queen. The d-pawn is doing good work shielding the Nd5 which cooperates with the Queen along the diagonal.

Black is running out of options and goes for activity with 33. ... Ba4. White tightens the screws with 36. g4 ..., and after 38. Bg4 ..., I think black should have exchanged. 38. ... Bxd5, 39. cxd5 b5, and all is well, although those white d-pawns gotta go!

Instead, 38. ... Bd7, causes a whole cascade of exchanges culminating in 43. Qxe4 ..., which had to feel good. White has an extra pawn and stands better because of his centralization.

45. Qh7+ ..., and 46. Rf1+ ..., demonstrate white's superior mobility and the black King's lack of safety. 50. Rf6 ..., gives black the choice of losing the King or the Queen; he resigns.

The outcome shows that 13. ... e4?, was rash, and that 26. d6!..., was justified. Keres' defensive resources were strained; he cracked. This was important in match-terms.

30 Qc1 postpones the thrust Nc7 to uncover the Rook on d1. The Rook can now go to d6 after Nc7. On an immediate 30 Nc7 Bxc7 31 dxc7 Ba4 the Rook on d1 can't go to d6 as it is obstructed by White's Queen.

38....Bd7 obstructs Black's defence of the b7 pawn but on 38...b6 39 Bxf5 Rxf5 40 Rxf5 Qxf5 41 Ne7+ Bxe7 42 dxe7 White has a winning attack, as White is playing with an extra bishop on the black squares while Black's QB does nothing on the white squares. One threat is Bd6 followed by Rd1-f1-f8.

40 Qb1 proposes an exchange of the d6 pawn for Black's e4 pawn following which White's Queen occupies the dominating central post of e4.

49 Rf6 shows a snapshot of Spassky's attacking skill in action. The Rook attacks the point e5 as well as the point f6, threatening to occupy either point. Black's KB covers e5 by 49...Bd6 whereupon the Spassky moves the Rook to the point f6 and now Black's Queen is unable to defend both the bishop and the Rook.

With 29 Nb5 the N will reach d5 in three moves by means of the manoeuvre Nc3-b5-c7-d5 instead of in one move by 29 Nc3-d5. However an immediate 29 Nd5 exposes the d6 pawn to attack after 29...f4 30 ef Nf5. 30 Qc1 postpones the thrust Nc7 to uncover the Rook on d1. The Rook can now go to d6 after Nc7. On an immediate 30 Nc7 Bxc7 31 dxc7 Ba4 the Rook on d1 can't go to d6 as it is obstructed by White's Queen.

38....Bd7 obstructs Black's defence of the b7 pawn but on 38...b6 39 Bxf5 Rxf5 40 Rxf5 Qxf5 41 Ne7+ Bxe7 42 dxe7 White has a winning attack, as White is playing with an extra bishop on the black squares while Black's QB does nothing on the white squares. One threat is Bd6 followed by Rd1-f1-f8.

40 Qb1 proposes an exchange of the d6 pawn for Black's e4 pawn following which White's Queen occupies the dominating central post of e4.

49 Rf5! shows a snapshot of Spassky's attacking skill in action. The Rook attacks the point e5 as well as the point f6, threatening to occupy either point. Black's KB covers e5 by 49...Bd6 whereupon the Spassky moves the Rook to the point f6 and now Black's Queen is unable to defend both the bishop and the Rook.

At the cost of repeating a part of a previous remark, in this match Spassky's performance against Keres attained a result that could have been forecast from Bobby Fischer at his best.

One interesting "if" of chess history is what might have happened if Spassky had not submitted to Fischer psychologically in a backroom incident before the third match game at Reykjavik. In that case Spassky might have drawn or even won the match.

With 13...e4 Keres hopes that Spassky will open lines whilst Keres is ahead in development.

Spassky does no such thing. He closes the e file by f4 and when Keres tries to open lines by 14....g5 Spassky declines to play 15 fxg5 and withdraws his bishop by 15 Bg3 instead.

Spassky will open lines by 19 fxg5 only after he has completed his development and it is he who will benefit from the opened lines.