Ponziani scheme

The world championship qualifier, known as the Candidates’ tournament, should now be underway in London. (For details see the website worldchess.com/candidates.) The favourite is Magnus Carlsen, who has identified Lev Aronian of Armenia as his most dangerous rival according to an interview in the Guardian with Stephen Moss. If Magnus fails to rise to the occasion, I favour Vladimir Kramnik, who usually plays well in London, where he was crowned world champion in 2000 when he defeated Kasparov.
 
One of Carlsen’s great strengths is his ability to adopt seemingly harmless openings and then manoeuvre endlessly until the opponent cracks. A case in point was his victory with the antediluvian Ponziani Opening, which he used to great effect at Wijk aan Zee earlier this year.
 
Carlsen-Harikrishna: Wijk aan Zee 2013; Ponziani Opening
 
1 e4 e5 2 Nf3 Nc6 3 c3 Nf6 4 d4 d5 Here I would be inclined to play the sharp 4 … Nxe4 5 d5 Bc5 6 dxc6 Bxf2+ 7 Ke2 bxc6 with distinct compensation for the piece. When Carlsen found himself on the black side, Hou Yifan-Carlsen, Wijk aan Zee 2013, he tried 4 … exd4 5 e5 Nd5 6 Bc4 Nb6 7 Bb3 d5 8 cxd4 Bg4 9 Be3 f6 10 0-0 Qd7 with a balanced position. 5 Bb5 exd4 5 … Nxe4 was seen in an old game also played in London: 6 Nxe5 Bd7 7 Qb3 Nxe5 8 Qxd5 Qe7 9 Qxb7 Bxb5 10 Qxa8+ Kd7 11 dxe5?? (correct is 11 Qd5+, keeping the advantage) 11 … Qxe5 12 Be3 Bc5 (sacrificing the second rook) 13 Qxh8 Nxf2 14 Kd2 Bxe3+ 15 Kc2 Qe4+ 16 Kb3 Qa4 with a spectacular mate (Wayte-Ranken, London 1890). 6 e5 Ne4 7 Nxd4 Bd7 8 Bxc6 bxc6 9 0-0 Be7 10 Be3 0‑0 11 Nd2 Nc5 12 b4 Nb7 13 f4 a5 (see diagram 1) 14 f5 One might have expected the solid 14 a3. Instead, Carlsen flings caution to the winds, sacrifices his entire queenside and aims directly at the black king. 14 … axb4 15 cxb4 Bxb4 16 Qg4 Bc3 17 Rac1 Bxd4 18 Bxd4 Rxa2 19 e6 f6 If White now plays 20 exd7 Rxd2 is fine for Black. 20 Nb3 Be8 21 Nc5 Nd6 22 Qf3 Qe7 23 Rf2 Ra5 Normally when material ahead one should trade pieces but there is nothing wrong with the text. 24 Nb3 Rb5 25 Bc5 Bh5 If now 26 Qxh5 Rxb3. 26 Qc3 Qe8 27 Qe3 Qa8 Black begins to crack under the pressure of defending his weak doubled pawns and coping with the passed white pawn on e6. 27 … Ne4 is a better try when the situation would remain obscure. 28 Nd4 Rxc5 29 Rxc5 Ne4 30 Nxc6 Nxf2 31 Kxf2 Qa2+ 32 Kg3 Re8 33 h3 Qa6 34 Qc3 Be2 35 Rxd5 Bb5 36 Nb4 Qb7 37 Qc5 Ba4 38 Rd7 Qe4 39 Rxc7 h5 40 Kh2 Kh7 41 Qf2 Rg8 42 Na6 Be8 43 Rc5 Qd3 44 Nb4 Qd6+ 45 Kh1 Qd1+ 46 Qg1 Qd6 47 Nd5 Rf8 48 Qd4 Kh8 49 Rc8 Bc6 and  Black resigned (see diagram 2) … without waiting to see the ingenious 50 Nxf6! which wins at once as 50 … Qxd4 51 Rxf8 is mate.
 
Last Saturday would have been Bobby Fischer’s 70th birthday. This week’s puzzle is a tribute to one of the greats of chess.