Round 1
Van Dijk underestimates the forthcoming attack on piece 27.
22x31 30.36x27 20x29 31.33x24 11-17! 32.47-41 2-7!
This is more accurate than ≡ 17-22 33.41-36 22x31 34.36x27 2-7 35.39-33 7-11 36.35-30 8-12 37.30-25 12-17 38.33-29, although the endgame after 17-22 39.29-23 18x20 40.25x14 22x31 41.14-10 11-17! 42.32-28 21-27! doesn't look safe for white either.
Note that the defense ≡ 33.39-33 is impossible due to the combination 15-20 34.24x15 4-10 35.15x4 7-11 36.4x22 17x50.
≡ 17-22 34.41-36 22x31 35.36x27 7-11!
A breakthrough on the left white wing is unavoidable now.
36.33-28 26-31 37.37x17 11x31 38.39-33 16-21 39.44-39 6-11 40.39-34 11-17 41.45-40 8-12 42.24-19 21-27 43.32x21 17x26 44.33-29 31-37 45.42x31 26x37 46.29-23 18x29 47.34x23 37-41
Round 2
It was safer to play ≡ 20-25 in order to build a fork formation after 36.45-40 14-20. In the game the development of the black piece on 15 becomes problematic.
≡ 36.45-40! 20-25 37.40-34 14-20 38.34-30 25x34 39.39x19 13x24 40.43-39
The position is still a draw, but it is tricky for black because of the passive formation 15/20/24.
11-17 41.39-34 7-12 42.33-28 20-25 43.32-27 8-13 44.37-32 13-19?
The decisive mistake. It was necessary to play ≡ 6-11 45.27-21 11-16. Then 46.32-27 is harmless because of 24-29! 47.34x23 13-18 with a draw.
≡ 45.38-33! 6-11 46.27-21! 11-16 47.32-27 15-20 W+
Round 3
Now Groenendijk decides the game using an unconventional Coup Philippe.
16-21! 17.26x17 24-30 18.35x24 20x38 19.42x33 25-30 20.34x25 23-29 21.33x24 19x30 22.25x34 18-22 23.27x18 13x35 and black won the piece on 17.
Round 4
This is the start of an instructive strategy against the black right wing.
Van Dijk doesn't mind that his right wing gets obstructed, but this turns out to be quite dangerous.
20.34-29 3-8 21.42-37 1-6 22.48-42!
White denies his opponent the exchange after ≡ 22.40-34 17-22 23.28x17 12x21 24.16x27 18-23 25.29x18 13x42 26.48x37.
≡ 20-25 23.29x20 15x24 24.50-44! 4-10 25.40-34 24-30
After ≡ 10-15 white plays 26.34-29! and black has nothing better than 18-22 27.29x20 15x24 28.28-23 19x28 29.32x23 with a winning advantage for white.
≡ 26.35x24 19x30 27.45-40 30-35 28.34-29?
After all the hard work Terwel fails to deal the final blow. Using ≡ 28.28-23! 18x29 29.34x23 white could bring the positional threat 30.37-31 36x27 31.32x21 into play. Obviously black can't allow this lock of his right wing. But ≡ 17-22? doesn't help because of 30.37-31! 36x27 31.32x21 13-19 32.40-34 19x28 33.21-17 12x21 34.16x18 8-12 35.33x22 12x23 36.38-33! and the black piece on 23 can't be defended. And also ≡ 13-18 30.39-34 18x29 31.34x23 17-22 32.37-31 36x27 33.32x21 is not possible because of the combination 11-17 34.23-19 14x23 35.33-28 23x32 36.38x18 12x23 37.21x5.
In the game Van Dijk freed the pieces on his right wing using the exchange ≡ 17-22! 29.28x17 11x22.
© Wieger Wesselink https://10x10.org