Rybka in Dutch Open Computer Chess Championship 2006

By Jeroen Noomen


Round 1: Rybka - Loop 1-0
A very interesting game, from a theoretical point of view. The line with 13... Ne8 is hot in computerchess and it leads to very complicated positions. Some lines are a real minefield, so I had to come up with an idea to play it safe as white. Black constantly has mating power available, with queen and rook on the a-file, the knight that can hop to b5 via c7 and not to forget the thrust d6-d5! I think with 22.Qg2! and 24.Rd5! white takes the sting out of the attack and emerges with a slight edge. With the black rook gone from the a-file and d6-d5 stopped forever, white need not worry about an attack anymore. Loop felt unhappy and rushed to exchange queens, but that meant white had a beautiful passed pawn on a3, supported by a strong bishop. Rybka played this ending strongly and gave Loop no chance. A clean win against one of our main rivals, a good way to start the tournament.

Round 2: Shredder - Rybka 0-1
Needless to say that after Turin I was very eager to win this game. Rybka played a solid Sicilian and had no problems after book was over. Shredder sacrificed a pawn to keep the black king in the centre, showing a +0,50 score. But this was really a misevaluation. Rybka already felt better as black and when Shredder started to sideline pieces (Qe3-h6-h7 for instance), it was all over quickly. Rybka gave a mate in 20 announcement at move 46. Sweet revenge (sorry, Ernst!).

Round 3: Rybka - Hiarcs 1-0
Another Najdorf with Hiarcs deviating from the Loop game. But IMO 10... Qc7 and 11... Rc8 cannot trouble white. With black's white squared bishop gone, the black minors passive at e7 and h5 and a firm white grip on the square d5, black can only wait and see what white will do. Rybka took some time to decide on action, but the pretty 30.Na1! - heading for d5 - increased the white advantage. Still, Hiarcs put up a tough fight and the ending needed precise play. We really wondered why Hiarcs gave away its g-pawn so easily at move 62, after that the game was over.

Round 4: Deep Gandalf - Rybka 0-1
The fourth Sicilian in a row, and no problems for black after leaving book. 10... Qa7! prevents a bishop trade by 11.Be3 and equalises. Suddenly Gandalf put oil on the fire with the questionable thrust 11.g4?! Black lost her castling rights, but white was in trouble right away. At move 17 white surely had to exchange twice at b7, hoping to escape in a worse endgame, but 17.Kd1? made matters worse. The rest of the game was a real Rybka demonstration, leading to the shortest win in a mere 28 moves. Anticipating 29.Bc3 Rybka announced mate in 15, so Gandalf's operator resigned.

Round 5: Rybka - Fruit 1-0
Another topical line, the Anti-Meran with 7.g4. This leads to lively play. IMO 10... cxd5 is questionable, while 15... exd4? is probably already the losing mistake. 15... Kh7 was necessary, but white is better anyway. Rybka played the resulting ending flawlessly and cashed in another win after performing some nice rook manoeuvres.

Round 6: The Baron - Rybka 0-1
A quiet opening line suddenly led to a closed position, when both programs decided to swap a lot of pieces but no pawns. White's 24.g4?! meant that only black had chances to go for a win, connected with the plan f7-f5. Rybka decided to wait and see and I was already making myself up for a very long game. Then The Baron helped us out by playing 55.Bxg6? that immediately led to a lost position. The Baron was already in mild time trouble and couldn't evaluate properly what was wrong with its decision. A tough game.

Round 7: Rybka - Isichess 1-0
In the opening - a Ruy Lopez - Rybka decided to sacrifice a pawn for positional compensation. Isichess had to play very carefully to avoid being entangled, but failed to do so. 24... Nh5? was a clear mistake and 28... f5? was something the black position couldn't take anymore. Still, Rybka finished the game in nice style, with an excellent exchange sac 33.Rc6!

Round 8: Rybka - Deep Sjeng 1-0
A Petroff was played 15 moves out of book and after 15.Bg5 black already has slight problems. Sjeng decided to get rid of the pressure by giving away a pawn, but then the game was essentially already over. With 57.g5! and 58.f6! - boxing in the black bishop - the finish was cute. Funilly enough Rybka operator Hans van der Zijden saw it already coming and when we decided that it was winning, Rybka agreed and jumped to +9.

Round 9: The King - Rybka 0-1
The King played the English as white. Who could have thought that this quiet opening would end in such a tactical fight! 12... Bh3 was played from the book (through a transposition of moves) and in practice white never took the bishop, as the black queen is very strong on h3. The King was happy to swap anyway and proceeded with 14.Nd5, asking Rybka 'prove your point'. This duly came: 14... Ng4! leads to a strong attack and when The King took the bait on c7, the game was already over. 15... f5! and the manoeuvre Nd5-c7-e6-g5 were pretty moves, underlining why white shouldn't capture on h3. I haven't seen The King losing so quickly very often, in the earlier days it was The King that was crushing the opponents like this! At move 24 we had yet another stunning mate announcement, this time in 18 moves.

So Rybka scored an amazing tournament victory, winning al her games. In a sense it was the perfect tournament: a great engine, a superb machine (a big thank you to Joe Soney is in place here!) and the openingbook worked fine. Normally you always have at least one bad game in a tournament, but here all went smoothly. I want to thank:

1. The organisers for yet another well organised and super relaxed tournament in Leiden
2. Joe Soney for making it possible to play on his machine (yes, it is a monster!)
3. Theo van der Storm for helping me out with the internet connection
4. All the participants, it was nice to meet you and the atmosphere was absolutely relaxed and fine

Second place went to Loop, that played an excellent tournament. Third came Hiarcs, a deserved and fine performance. Fruit was fourth and - like Loop and Hiarcs - only lost to Rybka. It is good to see Fabien Letouzey returning to the scene!

See you next time!





tournament site


brief game comments by Vasik Rajlich


all games from tournament


Rybka games (with Rybka search info)