Last weekend the Erding tournament was held. This tournament has a long tradition among Austrian tournaments. Personally, this year marked my 9th participation, and my 9th time winning a prize in Erding 🙂
Although I finished 1st with a 5:0 score, while outranking my opponents by ~120-400 rating points, most of my games were rather eventful. Below I present several key moments in each game.
Round 1 (I was Black): White has cash all over the board that Black needs to compete against with the right side moyo. You can see both players have a floating group, and Black is extra weak on the left side. What’s the appropiate strategy to take here?
Round 2 (White): This game has been uneventful up until now. White failed the invasion at c8, so Black might be leading slightly after grabbing the big move at 1… if nothing happens.
Round 3 (Black): Some crazy furikawuri happened on the Western hemisphere of the board. The game might be even if I hadn’t played attach and hane. :S
White to punish Black’s combo.
Round 3, part 2: After Black’s blunder in the previous diagramme, the game became pretty depressing. Until White pushed innocuously at 7.
Black to re-punish White.
Round 4 (Black): White started an unreasonable ko and seeks compensation with 1 and 3. The next move for Black is sort of important.
(Note that there were white stones inside each of Black’s ponnukis.)
Round 5 (White): White tried a stylish combo to handle the daidaigeima extension on the left. But if White only attaches under at c12, Black’s corner is sort of huge. (Later Black would still have the hane at c11 to harass White’s entire group.)
White should strive for a better result.
Round 5, part 2: Then the game proceeded peacefully without any real close combat. There are two key points in the game now, which one would you take?
Here is what happened in the games. Let’s call these diagrammes “solutions”, but if you find better moves, feel free to tell me.
I think it was the correct choice to disregard the left group to grab the keima at 1, lest White tigers at A. Basically it solves the floating group and builds the right side at the same time.
White kept putting pressure on the scattered stones on the left. Black again seizes sente after exchanging the keima at 6, for another moyo move at 10.
In the end the left group suffered a little, but did not get annihilated while White did not do significant damage to the moyo. So Black’s strategy to grab several building moves became succesful.
Variation: Regardless of whether Black’s strategy was an overplay or not, if Black had spend a move on the left group (that does not fix it completely), White’s tigermouth at 2 would have been devastating for the right side. I judged that this way Black could not win the game.
To Black’s two-space jump, White had prepared the crosscut shown in the diagramme.
Black captured one stone and let White close in his group.
Black had to take gote to connect the big group home, and finally White 10 shows his true colours.
White managed to connect back the previously failed invasion in ko. I won the ko by using threats in the upper right and finally the territorial balance tilted to my favour.
Variation: Note that if Black had insisted on cutting off the stones, Black’s outside group would have got in trouble thanks to the wall White got.
When I invaded at c8, I did not realise that nothing worked without those stones. Maybe Black’s jump at m14 should have defended this aji in some way.
White simply played the most straightforward atari-atari sequence and Black’s shape collapsed.
This game was full of mistakes from both sides:S I guess the players were tired playing the third game on the same day.
Round 3 #2:
To White’s push at r5, Black found the golden opportunity to turn it into a bad move. After the hane at 1 and blocking at 5 White became locally dead.
In the end White’s exchanges starting from r5 became a pass. Without this sequence, if Black had wanted to achieve the same result, Black would have needed to spend a move. This mistake proved to be fatal as White couldn’t turn back the game anymore.
Not only was the ko unreasonable, White’s threat did not work well either. I bumped out the stone immediately which was surprisingly severe.
In conclusion, White should have put the q12 stone at s12 during the ko threat, in whichever order.
Variation: Descending at 1 would mean admitting the mistake. Black can fix the shape in sente and continue fuseki.
Later Black’s s12 connection would still threaten White’s whole group, but this is probably as much as White can reasonably get.
Variation: Double-hane doesn’t seem to work well. Black makes two eyes inside and White has several problems to solve.
In a fight, Black’s ponponnuki would be extremely useful.
In the game White extended and Black crawled himself alive and cut at 10.
White again has several problems. In the end the upper group struggled a little and passed away which ended the game in one strike.
In this game both players made inconspicuous global mistakes that somehow cancelled each other out. In one of the only close combats of this game, White’s hane 1 and nobi 3 is a key combo.
Perhaps Black 2 should be at 3. It would force White to come back at c12, though the exchange White 1-Black 3 would be a territorial gain.
In the game Black connected at 1 and White made life in the corner. After Black pulled out the cutting stone with 5, I used the aji at A to get consecutive moves at B and C.
Not sure who was better afterwards, but as far as I can see, any other move would have led to a bad result for White.
Variation: Black could have considered inserting 1-2 before connecting at 3. In this case it would become worse for White to live in the corner, so I would have taken the other side and connected with a better shape (compared with attaching under).
Round 5 #2:
Variation: One move I really wanted to play was the kosumi at 3-3. Black would definitely keima at 2 and I had no idea what to do next.
According to my counting at the time, if White chooses to enclose at m12, Black’s territory is slightly bigger than White’s…
Which is why I turned at 1 in the game. Unfortunately Black was smart to play 3-3 immediately :S
So I initiated an unclear aerial fight starting at 9. It is aiming at A and a move around B to “attack”, maybe capture a part of Black’s floating group.
No idea which of these two diagrammes was better. In the end it still became a sort of close game, and I won after Black’s endgame was too slack.