Dutch Championship 2017 Urk round 6

Jitse Slump - Martijn van IJzendoorn 1-1

1.32-28 17-21 2.33-29 11-17 3.39-33 21-26 4.44-39 17-21 5.38-32 6-11 6.43-38 20-25 7.49-43 1-6 8.50-44 14-20 9.29-23 18x29 10.34x14 10x19 11.31-27 5-10 12.37-31 26x37 13.42x31 21-26 14.47-42 26x37 15.42x31 11-17 16.31-26 19-24 17.39-34 13-18 18.44-39 9-13 19.41-37 3-9 20.27-21 16x27 21.32x21 9-14 22.46-41 14-19

diagram 2
diagram 1

23.21-16(?)

As grandmaster Martin Dolfing explained on Toernooibase, it would be preferable to leave 21 in place and continue with 23.37-32 10-14 24.41-37.

10-14 24.37-32 24-30 25.35x24 20x29 26.34x23 18x29 27.33x24 19x30 28.41-37 30-35 29.40-34 13-18 30.38-33 14-19 31.43-38 18-23! 32.45-40 35x44 33.39x50 8-13

diagram 2
diagram 2

34.48-43?

White must operate very carefully to survive this position. The best way to achieve this was using 34.36-31! 15-20 35.48-43! 20-24 (not 12-18? 36.34-29 23x34 37.33-29 34x23 38.28-22 18x36 39.37-31 36x27 40.32x1 19-24 41.1x40 24-29 42.40x9 4x13 with a draw) 36.43-39 4-9 37.31-27 and black has no better than the combination 25-30 38.34x25 24-29 39.33x24 19x30 40.28x8 12x3! 41.25x34 17-21 42.26x17 7-11 43.16x7 2x44 44.50x39 with a draw.

12-18 35.37-31 4-9 36.50-44?

Here the difficult to find sacrifice 36.34-30 25x34 37.31-27 17-22 38.28x17 7-11 39.16x7 2x31 40.36x27 was a safer way to make a draw.

7-11 37.16x7 2x11

Now white loses a piece because of the threat 25-30 34x25 23-29 33x24 19x30 25x34 17-21 26x17 11x42.

38.34-29 23x34 39.31-27 18-22(?)

It might be the case that this spoils the black win. But even a variant like 18-23 40.27-21 13-18 41.21x12 18x7 42.28-22 9-14 43.22-17 11x22 44.32-28 23x32 45.38x18 25-30 46.26-21 30-35 47.21-16 results in a disappointing draw.

40.27x18 13x22 41.43-39 34x43 42.38x49 9-13 43.32-27 22x31 44.36x27 13-18 45.27-21 17-22 46.28x17 11x22 47.21-16?

This move is losing. White had to wait a move with 47.44-39 19-23 48.21-16 22-27 49.26-21 27-31 50.21-17 etc.

22-27 48.33-28 18-23 49.26-21 23x32 50.21-17 32-37 51.17-12 37-42 52.12-8 42-48 53.8-3 27-32 54.44-40 19-24 55.3-8 48-30 56.8-17 24-29 57.40-35 30-24 58.17-3 24-2 59.3-12! 29-33?

Black needed to avoid the exchange of the kings using 32-37 60.12x45 2-13, and now for example 61.49-44 37-42 62.44-39 42-47 63.39-34 13-2! 64.45-50 15-20 65.50-45 20-24 etc.

60.12-7! 2x11 61.16x7 6-11 62.7x16 33-38 63.16-11 15-20 64.35-30 25x34 65.49-44

Ron Heusdens - Nico Knoops 1-1

1.32-28 17-21 2.37-32 11-17 3.31-26 7-11 4.36-31 19-23 5.28x19 14x23 6.33-28 21-27 7.31x22 18x27 8.28x19 13x24 9.32x21 16x27 10.41-37 1-7 11.39-33 10-14 12.44-39 5-10 13.50-44 27-31 14.37-32 31-36 15.42-37 9-13 16.46-41 17-21 17.26x17 11x22 18.48-42 7-11 19.34-30 12-18 20.30x19 14x23 21.35-30 20-25 22.32-28 23x32 23.37x17 25x34 24.40x29 11x22 25.41-37 10-14

diagram 2
diagram 3

26.45-40

White has a small advantage, due to the weak piece on 36. Interestingly Heusdens now consistently works on an attack against the black right wing.

13-19 27.40-34 14-20(?) 28.38-32 19-23 29.32-27 22x31 30.37x26 8-13 31.42-38 6-11 32.33-28! 23x32 33.38x27 11-17(?) 34.44-40! 20-25 35.29-23 18x29 36.34x23 4-9 37.39-33 17-22 38.27x18 13x22 39.26-21 15-20 40.43-39 9-14 41.49-44 14-19 42.23x14 20x9 43.33-28! 22x33 44.39x28

diagram 4
diagram 4

2-7?

If the pieces on 36 and 47 are ignored, white has a considerable lead in tempi. In fact the black position is already so compromised that there were only two possible moves left: 9-14 and 25-30. And both of them are not very logical since the natural impulse is to strenghten the weakened wing.

45.40-35?

Heusdens doesn't spot the winning move. First of all, one has to recognize that immediately 45.28-22? doesn't work due to 25-30! 46.21-16 3-8 47.22-17 9-14 etc. So the piece on 25 needs to be blocked, but Heusdens chose the wrong way to do it. After 45.40-34! then a few variants are 1) 9-13 46.28-23 3-9 47.21-17 9-14 48.34-29! 13-19 49.17-12 19x28 50.12x1 28-32 51.1-23 W+ or 2) 9-13 46.28-23 7-12 47.21-16 12-17 48.44-40 3-8 49.34-29 8-12 50.29-24 W+.

9-14 46.28-23 14-20 47.23-18 20-24 48.44-39 25-30! 49.21-17 3-8 50.17-12

Also 50.18-12 7x18 51.17-11 18-23 52.11-7 23-29 53.7-1 36-41 54.1x25 41-46 is insufficient.

8x17 51.18-13 7-12! 52.13-9 17-21! 53.39-33 12-17

Anton van Berkel - Wouter Sipma 1-1

1.32-28 17-22 2.28x17 11x22 3.37-32 6-11 4.41-37 12-17 5.33-28 22x33 6.38x29 7-12 7.43-38 19-23 8.35-30 20-25 9.40-35 14-20 10.38-33 10-14 11.45-40 14-19 12.50-45 4-10 13.42-38 10-14 14.30-24 19x30 15.35x24

diagram 5
diagram 5

2-7!?

Here an obvious plan for black would be 14-19 16.40-35 19x30 17.35x24 25-30 18.34x14 23x43 19.48x39 9x29 20.33x24 18-23 21.49-43 13-18 22.32-27. But Sipma starts a simple but effective long term strategy, by attacking the outpost on 24 multiple times and finally remove it.

16.48-43 5-10 17.46-41 14-19 18.40-35 19x30 19.35x24 10-14 20.45-40 14-19 21.40-35 19x30 22.35x24 9-14 23.44-40 14-19 24.40-35 19x30 25.35x24 3-9 26.33-28 18-22 27.29x27 20x40 28.39-34 40x29 29.28-22 17x28 30.32x34

diagram 6
diagram 6

12-18

The result of Sipma's strategy is that white suffers from an uneven piece distribution. It's not alarming yet, but it's clear that white will have to defend during the rest of the game.

31.37-32 11-17 32.47-42 7-12 33.41-37 9-14 34.43-39 14-19 35.39-33 15-20 36.31-26 20-24 37.37-31 17-22 38.33-28 22x33 39.38x20 25x14 40.42-38 18-23! 41.34-30 23-29

diagram 9
diagram 7

42.27-21!?

Instead of reorganizing his defense with the backward exchange 42.38-33 29x38 43.32x43 Van Berkel decides to launch a counter attack on the black right wing. This looks quite dangerous due to the strong defender on square 1, but Van Berkel will prove that his decision was correct.

16x27 43.31x22 12-18 44.22-17 19-23 45.26-21?!

A daring piece sacrifice. The normal 45.30-25 29-33 46.38x29 23x34 47.49-44 13-19 48.26-21 19-24 49.21-16 24-30 50.17-11 30-35 51.11-7! 1x12 52.16-11 was also sufficient for a draw.

29-33 46.38x29 23x25 47.17-11 25-30 48.11-6 30-34 49.49-44 14-19 50.21-16 19-23 51.16-11 23-29 52.32-27 18-23

After 13-19 white can make a draw using 53.11-7 1x12 54.27-22 18x27 55.6-1.

53.27-22 8-12 54.36-31 29-33 55.22-17 12x21 56.11-7 1x12 57.6-1 13-18 58.1-6 34-39 59.44-40 23-28 60.6-17 39-43 61.17x26 33-38 62.26x3 38-42 63.3-25 42-47

© Wieger Wesselink http://10x10.org