World championship 2013 preliminaries round 2

Samb undermined the black centre with 31.27-22! 18x27 32.32x12 8x17 33.38-33 9-13 34.49-43 17-21(?) The central move ≡ 13-18 was more logical here. ≡ 35.39-34! It is important that 13-18 36.34-29 3-9 37.29x20 15x24 38.45-40 18-23 is unattractive for black because of 39.40-34! 23x32 40.34-29. ≡ 24-30 36.35x24 19x39 37.43x34! Black has problems now, due to the inactive pieces on 16 and 21. These pieces can advance towards 36 an 37, but they will not get past the gatekeepers on 47 and 48. 1-7 38.45-40 7-12 39.33-29 13-19 40.34-30 3-9 41.40-35 9-13 42.48-42 21-26 43.42-38 16-21? This move is losing. Black should have played ≡ 26-31! The subtle difference with the game is that after the variant 44.38-33 12-18 45.30-24 19x30 46.35x24 14-19 47.24-20 15x24 48.29x20 18-23 49.20-15 23x32 50.15-10 black has the trick 19-24

51.10-4 32-37! 52.4x36 37-41! with a draw. ≡ 44.38-33! 12-18 45.30-24 19x30 46.35x24 14-19 47.24-20 15x24 48.29x20 18-23 49.20-15 23x32 50.15-10 Now black is one move too late. 26-31 51.10-5 31-37 52.5x23 21-27

Mejia was in trouble against Nossov, because after 18-23 24.47-42 23x32 25.33-29 24x33 26.39x37 the black outpost on 27 will get lost. ≡ 6-11? This is losing. With the unconventional move ≡ 2-7!! black could have defended his position. This is possible because after 24.33-29 24x42 25.48x37 22x33 26.31x2 black can counter with 18-23! 27.39x28 23x41. In the game white gained a winning advantage after ≡ 24.26-21 17x37 25.28x6 27-32 26.38x27 37-41 27.6-1 2-7 28.27-21 41-46(?) 29.35-30 24x35 30.21-17 12x21 31.1x34 19-24 32.43-38 8-12 33.34x1 14-20 34.25x14 46x5 35.38-32 5x41 36.33-29 24x33 37.39x28 41x45 38.44-40 45x7 39.1x26 35-40 40.26-17 13-18 41.17-50 40-45 42.49-44 18-22 43.36-31 9-13 44.31-26 3-8 45.26-21 22-27 46.21x32 13-18 47.32-27 15-20

After 14x23? Amrillaew missed a great opportunity. With the temporary sacrifice 35.21-17! 12x21 36.40-35! 21-26 37.35x24 he could have taken the black piece on 23 under a heavy attack. For example after 8-12 (to make a king after 38.33-28? 15-20! 39.28x17 20x49) ≡ 38.44-40 13-18 39.34-30! 25x34 40.39x30 12-17 41.40-35 10-14 42.24-19! the piece would be lost. In the game after ≡ 35.40-35 13-18 36.35x24 23-29 37.34x23 18x20 he still got some opportunities to win the game, but he did not succeed.

Mbongo became the vicitim of a well known openings trick 21-26?? 6.33-29! 26x37 7.27-22 18x27 8.29x7 1x12 9.32x21 16x27 10.41x21 and white won the game.

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