Stakhanovite

Before leaving the topic of the 50th anniversary of the 1967 tournament to mark the half-century of the Russian revolution, I must mention the Hungarian grandmaster Lajos Portisch, another hero of that prestigious competition. (Leonid Stein being the overall winner.) Portisch was famed for his immense hard work and profound erudition in the openings. At Moscow he outgunned both the reigning world champion, Tigran Petrosian, and his recent challenger, the future champion Boris Spassky, as a result of his Stakhanovite exertions in the field of openings analysis.
 
Portisch-Spassky: October Revolution, Moscow 1967, Nimzo-Indian Defence
 
1 d4 Nf6 2 c4 e6 3 Nc3 Bb4 4 e3 b6 5 Nge2 Ba6 6 Ng3 0-0 7 e4 Nc6 8 Bd3 d5 This move is not seen any more, 8 … e5 being preferred. 9 cxd5 Bxd3 10 Qxd3 exd5 11 e5 Ne4 12 a3 Bxc3+ 13 bxc3 f5 14 Ne2 Played with the aim of rerouting the knight to a more active square, f4. White also has another, subtler idea in mind. 14 … Na5 Black is oblivious to White’s plan or he would have preferred 14 … Ng5 planning … Ne6. 15 h4 (see diagram 1) Now the enemy knight is badly cut off. 15 … Nb3 16 Rb1 Nxc1 17 Rxc1 f4 18 Qf3 Qe7 Surprisingly, this position had occurred previously in Portisch-Shamkovich, Sarajevo 1963. That game saw a better defence from Black: 18 … c5 19 Nxf4 and now 19 … b5! (instead of 19 … Rc8 as played) would have left Black only slightly worse. The point is that 20 Qe3 (as played in the main game) is ineffective due to 20 … cxd4 21 cxd4 Qa5+. 19 c4 c6 20 cxd5 cxd5 21 Nxf4 Now White is a pawn up and the black knight on e4 remains vulnerable. 21 … Qd7 22 g3 Qb5 23 Qe2 Not 23 Qd3 when 23 … Qxd3 24 Nxd3 Rf3 gives Black counterplay. 23 … Qa5+ 24 Kf1 Qxa3 Although Black has regained material on the queenside, White is winning easily as the d-pawn is extremely vulnerable and White has a powerful central pawn mass. 25 Kg2 Rf7 26 Rc2 White plays safely but there isn’t anything wrong with 26 e6. 26 … Raf8 27 Rhc1 h6 28 Qg4 Qa4 29 e6 Rxf4 Desperation. 30 gxf4 Qxd4 31 Rd1 Qf6 32 Rc7 Nc5 Black’s final chance was 32 … h5 although after 33 Qxh5 Qxf4 34 Rf7 Rxf7 35 Qxf7+ Qxf7 36 exf7+ Kxf7 37 Rxd5 White should win easily enough. 33 f5 Qe5 34 Rxa7 h5 35 Qg6 d4 36 Re1 Qf6 (see diagram 2) 37 Qxf6 A more attractive finish is 37 e7 Qxg6+ 38 fxg6 Re8 39 Ra8! although it doesn’t really matter. 37 … gxf6 38 Kf3 d3 39 Rg1+ Kh8 40 Rgg7 Black resigns