Here there were many decisive continuations: 34...Qe6 and …h7-h6 (Chistyakov), 34...Kg6 (Ragozin) 35.Be5 Qxe7 36.Qf3 Nd7! 37.Qxd5 Nxe5 38.dxe5 Qc5+ or, finally, 34...Qa4! with the threat of …Qd1+ (Kmoch, Euwe) – I tried to find a defence after 35.Qf3!, but without success: 35...Qa1+ 36.Kh2 Qb2+ 37.Kg1 (37.Kg3 Qxc3!) 37...Qc1+ 38.Kg2 Qd2+ 39.Kg1 Qe1+ 40.Kh2 Qe6 41.Ba3 Qe4 and Black wins.

Denker’s inaccuracy apparently throws away the win – anyway, it gives White practical chances, which Euwe exploits simply splendidly!

35.Ba3! Qa4 36.Qd6 Qd1+ 37.Kg2 Qe2+ 38.Kg1 Qe3+ 39.Kg2 Qe4+ 40.Kg1 b5 41.Qd8 b4.

For the moment Denker is equal to the occasion: it was worse to play 41...Ne8?! 42.Qxa5 or, of course, 41...Qb1+ 42.Kg2 Qa2+ 43.Kg1 Qxa3?? 44.Qf8+ Ke6 45.e8Q+ Nxe8 46.Qxa3 and wins.

42.Qf8+ Kg6 43.cxb4 Qxd4+ 44.Kg2 Qe4+ 45.Kg1 axb4 46.Bxb4 d4 47.Ba5!

Euwå finds the only way to resist: the manoeuvre of his bishop to d8 with the threat of Qxf6+ and å8Q+.

47…c3.

The most obvious move. According to Denker, ‘47...Qe6 was better’, but after 48.Bd8! (with the threat of Qõf6+) 48…Qf7 49.Bb6! White would have gained a draw, for example: 49…d3 50.h4! gxh4 51.Be3 Qe6 52.Qh6+ Kf7 53.Qf8+ with perpetual check.

Also unclear is 47...Qe5 48.Kg2! (but not 48.Bd8? Qg3+ 49.Kf1 Qxh3+ 50.Ke1 Qh1+ 51.Ke2 Qg2+ 52.Ke1 Qg1+). Ànd 47...Qb1+ 48.Kg2 Qa2+ 49.Kf1! is right. (Sorokhtin) 49…Qxa5 (after 49….Qa4 50.Bd8! Qd1+ 51.Kg2 the terrifying threat Qxf6+!! forces Black to perpetual check) 50.e8Q+ Nxe8 51.Qxe8+ Kf6 52.Qf8+! Ke6 53.Qh6+ Kd7 54.Qxh7+ Kc6 55.Qg6+ with a simple draw. <…>

48.Bd8 c2??

Denker attaches as many as three question marks to this move and writes: '48...Qb1+! 49.Kh2 Qa2+ and …Qf7 would have won’. Let us check: 50.Kg1 (not 50.Kg3? Qf7 51.Bb6 c2 52.Qc8 Ne4+ or 51.Qxf7+ Kxf7 52.e8Q+ Nxe8 53.Bxg5 Ke6 and wins) 50...Qf7 51.Bb6! c2! (the only move) 52.Qc8! (also the only move) 52…d3 53.Qf5+ Kg7 54.Be3! Qxe7 (54…h6!?) 55.Qxd3 h6! (55...Qe5 56.Bxg5! Qxg5 57.Qxc2 is less clear) 56.Kf1 (56.Kf2?! Qc7 57.Bc1 Qh2+ 58.Ke1 Qg1+ 59.Qf1 Qd4 60.Qe2 Qc3+) 56...Qc7 57.Bc1 Qc6 58.Ke1, and the win for Black is not simple. If, say, 58...Qh1+ 59.Qf1 Qxf1+?! 60.Kxf1 Nd5 61.Ke2 Nf4+ 62.Kd2 Nxh3 there is the pretty 63.Bb2+ (but not 63.Kxc2? Nf2 and wins) 63...Kf7 64.Bd4! with a draw.

Euwe and Kmoch also gave 48...Qe3+ 49.Kg2 c2 50.Qxf6+ Kxf6 51.e8Q+ Kg7 52.Qd7+ Kf8 53.Be7+?! Qxe7 54.Qc8+ Kg7 55.Qxc2, and White has a difficult position, but the computer finds a draw immediately: 53.Qf5+! Ke8 54.Bxg5=.

49.Qxf6+! Kxf6 50.e8Q+.

Taimanov after 19 Qb2:
"In this critical position, where both sides have carried out their strategic plans (White - to break through in the centre, Black - to win a pawn), the chances are with White. He has a concrete plan of attacking with his e- and f-pawns. wher-as Black's counter-offensive on the queenside is usually too late."

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30. Bb4! Qe8 31. Qf4 h6 32. Qe5+ Nf6 33. Qc7+! Kg8 34. Be7! Nh5 35. Qxa7 +-

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