Lien : Chessbase

(1) Cossin,Sebastien (2494) – Sebbar,A (2290) [E99] 1st Int. Chess Open of Marrakech Marrakech (5), 28.06.2010 [Reeh,Oliver]

1.d4 Nf6 2.c4 g6 3.Nc3 Bg7 4.e4 0-0 5.Nf3 d6 6.Be2 e5 7.0-0 Nc6 8.d5 Ne7 9.Ne1 Nd7 10.Be3 f5 11.f3 f4 12.Bf2 g5 13.Rc1 Ng6 14.c5 Nf6 15.Nd3 h5 16.cxd6 cxd6 17.Nb5 Rf7 18.Nxa7 Bd7 19.Qb3 g4 20.Bb6 Qe7 21.Rc7 g3 22.h3 Ne8 23.Rxb7 Qh4 24.Rxd7 Rxd7 25.Nc6 Rb7 26.a4 Bf6 27.a5 Bd8 28.Nxd8 Qxd8 29.Rc1 Qd7 30.Nb4 Ne7 31.Rc6 A flashy move. [Very strong was the immediate 31.Ba6 ! ]

31…Nc8 32.Ba6 ? Now the abandoned back rank takes its toll. [32.Na6 was still good for White.]

32…Nxb6 33.Bxb7 Qxb7 ! [Less good would be 33…Rxa5 ? 34.Nc2 ! (34.Rxb6 ?? Ra1+ ) when White is fine again : 34…Qxb7 35.Qxb6 Qa8 36.Na3 ]

34.Nc2 Perhaps White had relied on this knight retreat : the square a1 gets protected and it looks as if he could collect the black Nb6 on the next move. [The knight was still taboo : 34.Rxb6 ? Qxb6+ ! 35.axb6 Ra1+ and mate.]

34…Qa6 !! Out of the pin (b-file) into the pin (6th rank) ! The threat 35…Qe2 jolts White out of his dreams : Black is winning – answer A).

35.Qxb6 [The two other captures were even worse : 35.Rxb6 Qe2 36.Qb5 Qxc2 ; or 35.axb6 Qa1+ ! ; The most stubborn was 35.Qc3 Qe2 36.Qe1 Qxe1+ 37.Nxe1 and now simplest is 37…Nxd5 ! 38.exd5 Rxa5 with a clear advantage in the knight ending.]

35…Qe2 ! Threatens 36…Qd1+ followed by mate.

36.Kh1 Allowing the retreat Qg1, but…

36…Qf2 ? Letting White off the hook. [The culmination of Black’s play would have been the deflection 36…Ra6 !! , when Black is winning : 37.Qg1 (37.Qxa6 Qd1+ ) 37…Rxc6 38.dxc6 Qxc2-+ ]

37.Na3 Saved !

37…Rb8 [Quite bad would be 37…Rxa5 ? due to 38.Qxf2 gxf2 39.Rc1 followed by 40.Rf1/41.Rxf2.]

38.Qxf2 gxf2 39.Rc1 Rxb2 40.Rf1 Re2 41.Kh2 h4 42.a6 Ra2 43.Nb5 Rxa6 44.Rxf2 Ra1 45.Rb2 Nf6 46.Nc3 Rc1 47.Ne2 Re1 48.Nc3 Rc1 49.Ne2 1/2-1/2