Lee Sedol - Gu Li, second encounter

Moves 1 to 10  

This is the second game in the Lee Sedol - Gu Li rivalry. Lee again plays White. Interestingly, up until the moves are exactly the same as in their first encounter. makes the kosumi which Gu Li made with in the first game, probably forestalling a counter that Lee had prepared since. emphasizes the top, while in the first game White put a stake into the right side. With the pincer of the game now develops completely differently.

Moves 11 to 20  

The two stars develop a complex variation of the bottom right corner joseki. We'll see how the fighting spreads across the board for the next 40 moves.

Moves 61 to 70  

After here, I (Dieter) have the impression that Black is better.

EdIV?: I had the same impression, however I read in a pro-commentary that W's shape is better than B's and that he therefor thought W was marginally ahead.

Moves 81 to 90  

When playing the peep of here, perhaps Gu did not anticipate , which is quite a move. If bamboos at instead ...

EdIV?: yes 81 is a big mistake, losing move of the game.

@  

... this will happen.

Moves 91 to 100  

So White breaks through at and a fight develops that only top professionals can predict (intuitively, perhaps).

Moves 131 to 140  

Of course, as could be predicted by amateur followers, it becomes a ko. Before starting the ko, increases the size of threats in the centre area.

EdIV?: B has no choice, he desperately lacks ko-threats.

Moves 141 to 150  

Similarly, White raises the stakes for Black in the lower left. At , the ko is started, i.e. responds to Black's atari by taking the ko. is a local ko threat in the sense that Black will save the largest part of his group and connect in the centre, dominating the board as a result.

Moves 151 to 160  

takes back the ko, is an obvious local threat. Then is a similar threat as the one mentioned in the previous diagram, but this time, more aji is left after the threat execution. Anyhow, White has no more local threats and captures the stones at the bottom. Black connects his centre stones, but we will see that the aji will play a role later.

uses the sente to harass the Black stones in the lower left, but it had been precalculated that they will live.

Moves 161 to 170  

lives. I find it hard to say now who is better. I'm inclined to still choose Black, but White seems to be a little more active at this stage of the game.

EdIV?: Actually B has fallen behind badly, W is ahead on on both development and territory. W got some solid points and has no real weaknesses, the areas that B got on the other hand can all be significantly reduced in sente and he still has some weak stones on the left.

Moves 171 to 180  

It seems like Gu Li wants to decide the game with another ko but this time he may have overestimated his chances.

EdIV?: the ko is an overplay, yes, but he has no choice, regular play won't cut it anymore.

Moves 191 to 200  

When resolves the ko without any compensation, the tables have been turned. White's top territory is gigantic. Perhaps Gu thought he could separate the left side and kill it.

However, he realizes he has to connect at . Otherwise, White can play there in sente due to the shortage of liberties at the marked points and the left side will live (according to Dieter's amateurish calculations):

@  

As said, is sente and now can start a ko. White has two local threats at a and b while Black has only one at ''c'. Perhaps White has to keep in reserve for an extra threat. Comments welcome here.

Moves 201 to 210  

While shows signs of despair, Lee Sedol takes command over the game and harasses Black's thin right side.

Moves 211 to 220  

With the top right corner becomes solid white territory and the game is decided.

Moves 221 to 228  

puts a smile on spectators' faces: it's Gu Li's habit to decide the game through another ko and Lee uses this weaponry against his rival to become. After the first ko threat at , Gu Li resigns.