World championship 2013 preliminaries round 9

Tolchykov - Derival 2-0
Andrei Tolchykov - Nicolas Derival 2-0 (2013)

Derival lost this 5x5 position after 13-18? He should have played the unexpected   21-27! 58.22x31 13-18! Then white cannot win, for example 59.32-28 16-21 60.37-32 26x37 61.32x41 21-27 62.41-36 27-32 63.28x37 18-23 etc. or   59.33-28 24-29 60.35-30 18-23 61.28x19 29-33 62.32-28 33x22 63.19-14 16-21 64.14-10 22-28!   58.22x13 21-27 59.32x21 16x27 60.13-9! 27-31 61.37-32 31-36 62.9-4! It works out perfectly well for white. 26-31 Since   36-41? is prevented by 63.33-29 24x33 64.32-28 33x22 65.4x47 W+   63.4-10! and black resigned.

Berichvili - Boomstra 0-2
Djoumber Berichvili - Roel Boomstra 0-2 (2013)

Boomstra needed to win to keep his hopes alive for a place in the final. He did that very convincingly. 17-21! 32.31-26 12-17! 33.44-39 20-24 34.30x19 13x24 35.39-34 8-13 36.45-40 18-22! 37.27x18 13x22 The white center is in a dangerous encirclement now. 38.34-29 14-19 39.29x20 15x24 40.40-34 9-13 41.34-29? This is certainly losing. But also after   41.34-30 13-18 42.48-42 22-27! the white perspectives for a draw are minimal.   10-15 42.29x20 15x24 43.48-42 22-27! 44.43-39 13-18 45.39-34 5-10 46.42-37 18-22 47.34-30 27-31! White is outplayed. 48.28-23 19x39 49.30x19 31x33 50.25-20 39-43 51.20-15 21-27 52.32x12 and white resigned.

Amrillaew - Ivanov 1-1
Mourodoullo Amrillaew - Artem Ivanov 1-1

After 18-23?! Amrillaew took a small combination using 42.38-32 27x38 43.48-43 38x49 44.45-40 49x35 45.34-30 35x24 46.20x9 4x13 47.15-10 At first sight this looks very dangerous for black. But Ivanov calculated a safe way to draw using 16-21! The idea behind this move is 48.10-4 28-32! 49.4x2 32x41 50.2x24 41-46 with a draw.   48.39-34 21-27! 49.37-31 This allows black to make a king, but there was no better alternative for white. 28-33 50.31x22 33-38 51.10-5 19-24 52.5-28 13-19 53.28x10 38-43 54.10-28 43-49 55.28-50 7-12

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