Lee Sedol - Gu Li Jubango, game 1

   

update: it may be better now to discuss the game at [ext] http://gogameguru.com/go-commentary-lee-sedol-vs-gu-li-jubango-game-1/

update: there is also a commentary by Rob Van Zeijst [ext] http://www.kiseido.com/printss/guliten1.html

I'm now merging the sgf's of these two greats with some of the live comments, published by the AGJ and notes from myself. I'm currently able to replay the game by heart well into the endgame.


I, Dieter, will try to keep the discussion at a very basic level and not pretend to know what's going on. However, some inputs are derived from the American Go Journal's rendition of the live commentaries by Cho Hanseungand Park Jeongsang, both 9p at the Hankuk Kiwon.


[Diagram]

Moves 1 to 10

B5 is a 4-4 low approach. It limits the development of the corner stone and undermines some of its stability. W6 is a basic development of two stones: the one space jump. It seeks development to that side, while providing a high degree of connectivity. W8 is an attachment as well as a diagonal development. White removes a liberty of B5 and makes it harder for Black to jump into the corner. B9 is a basic defensive move against such attachment. A hane would not be appropriate here, because White's group is strong. W10 is a splitting attack.


[Diagram]

Moves 11 to 20

B1 abandons the stones at the bottom side to create a new pole of development at the left. W2 checks that stone, expanding his potential territory in the corner while limiting the development of B1. Such a tsume is the most common way to attack a stone. W4 is a similar move, but due to the presence of black+circle it has no room for a base. Therefore we can see this move as a reduction. The stone may be sacrificed if the scale of Black's potential remains modest. B5 is another basic development with the one space jump. Normally, Black should attack in his sphere of influence, with a keima. However the situation is complex with all these scattered stone so some safety may be in order. W6 is such a keima, attacking Black's isolated stones. B7 is another safe development. W8 checks black+circle and combines a diagonal play with the keima of W6. The aim is to expand the scope of the attack on the two lone black stones. Locally, B9 would be played at a, but then b completes the encirclement. Therefore, B9 is an attachment, the basic move for creating something viable in a hostile sphere of influence. W10 deserves a diagram of its own.

unkx80: Players at a certain level should have the intuition that B5 is the only move. See diagram below.

[Diagram]

Why not hane

A hane at the outside is the common response to an attachment but then W2 separates two white stones in a manner that is considered painful. White is helping black.

[Diagram]

Why not cut

White can cut the black stones. Now black has two chains of solidly connected stones, while white's stones are connected in a crooked way. Although it is not easy to see, there are too many weak points in White's position this way: a and b, leading to c. It would not be possible to keep the attack going on all black stones, which is necessary for White to keep balance with the black sphere of influence on the right.

[Diagram]

Capped in

unkx80: If B5 plays the "more usual" knight's move, then W6 caps the black+circle stone in. At the same time, W6 more or less connects W4 with white+circle, forming some kind of influence and exerting more pressure on the two Black stones at the lower left corner. This position is disadvantageous for Black. Therefore, B5 must separate the white+circle and W4 by jumping out at W6. The difference is quite stark.

[Diagram]

Attacking keima

Dieter: I was actually referring to this keima attack. Not that it would occur to me spontaneously but I'm analyzing this pro game from a basic technique perspective, trying to understand the choice of each haengma in each situation. Here, although we can interpret the bottom as a black sphere of influence, the black advantage is at most one stone, so the choice of playing the safer one space jump is understandable.

unkx80: Oh, I see. I have no strong preference over the one-space jump or the two knight's moves you proposed, because the idea is similar. I don't know how basic or advanced this idea is though. This kind of idea deserves its own page on Sensei's Library, but I could not find it - is there already related material on the Library? In any case, please feel free to edit accordingly.

kb: I think the one-point jump is strictly better than the knight's move. The reasoning here is clear: when attacking two sides of equal strength, play honte as an indirect attack, making miai for the other player of defending both sides. One of honte's tenets is making oneself strong first, then fighting. This idea should be contrasted with a leaning attack, another type of indirect attack that should be used when one side is already stronger than another.

I am not sure if this idea exists on SL anywhere yet, but I have had pros teach me this technique as well as using it myself to great success in many games. I think this concept comes in at the low dan range. Once you see it in action, you will understand when to use the knight's move and the one-point jump for attack. It is certainly an element of haengma but I would appreciate a librarian's input if they know the word for this type of play.


[Diagram]

Moves 21 to 30

Black fixes his connection through B3 and B5, then moves out with a diagonal play. Let's discuss W2, W4 and B9.

[Diagram]

Hane at the head of two

The usual answer to a move like B1 would be W2, a hane at the head of two. In this situation this would probably lead to B3 and Black gets out quite comfortably. So White kept the attack going with a instead.

[Diagram]

Atari from the other side

If W4 ataris inside to cut through, Black will gladly capture two stones and get a good position at the left side. White can not allow such an even exchange in his sphere of influence.

[Diagram]

Simple hane

When White plays move 28 at W1 here, the common answer would be B2 then B4 to form a hanging connection. Black chose to apply the one two three principle and play B4 immediately. The omission of the B2-W3 exchange will leave more potential for him to still enter the corner.

[Diagram]

Moves 31 to 40

The sacrifice tactics of B1 to B9 require more advanced understanding and cannot be discussed from a perspective of basic technique.

[Diagram]

Moves 41 to 50

The one space jump of B3 is a basic move for defence. W4, the one space check? is a basic move for attack. B5, a large knight's move, is a sort of counter attack, but it has a higher degree of flexibility than a simple keima.

W6-B7 is a typical attachment-hane exchange, where White tries to establish a position in Black's sphere of influence. B7 gives some leverage for White at a next, but if Black would retreat to b instead of B7, then it's too easy for White.

W8 is a special move, trying to cut the large knight's move. Black's reply is not intuitive:

[Diagram]

Normal hane

The normal answer would be B2, to try and preserve the connection within the large knight's move. Probably this allows W3, giving White the choice to cut at a or b next.

[Diagram]

Moves 51 to 60

W2 is a leaning move: if Black plays the usual hane at a, White cuts through the small gap at b. White is looking at a chance to wedge at c. These are advanced tactics.

B9 is the slowest possible haengma: the solid stretch prevents a potential wedge.

W10 was criticized for bad timing. The local purpose is clear: a counter hane applies leverage to create a small position in Black's sphere of influence.

[Diagram]

Moves 61 to 70

We're in heavy middle game pro fighting now. From here we'll leave it up to pro commentators.


This is a copy of the living page "Lee Sedol - Gu Li Jubango, game 1" at Sensei's Library.
(OC) 2014 the Authors, published under the OpenContent License V1.0.
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