4-5 point 4-3 approach outside contact

  Difficulty: Intermediate   Keywords: Joseki
Outside contact  

B1 is not so often seen now in pro play, because it relies in one major variation on a ladder. Nowadays, joseki involving ladders may be experiencing a decrease in popularity. See Ladder strategy / Discussion.

Deviations from the sequence up to W4 are very rare.[1] Tenuki with W2 is also very rare: see 4-5 point 4-3 approach outside contact, tenuki.

After W4, it is expected Black will cut at a or b. White will capture the cutting stone and Black takes either territory or influence. W2 at b also.


On a few occasions in pro games, W1 is played. This continuation is typical: White's position is low, and Black has influence on the left side. By playing this way White does limit Black's choice.

Outside contact main line  

This is by far the most common variation, with Black taking the corner. Since white+square does retain some aji, follow-up plays here require careful thought.

White a is often played immediately, since White does not want to allow Black the severe play at b.

Variation - potential ko  

On the other hand Black can still play for influence here, with B1 instead of the cut at a (previous diagram). After W4 it looks like a ko: this is unlikely to be fought out (though it was in a game Rui Naiwei-Pak Chi-eun(B) 2001-02-12).


Assume W2, B3 elsewhere as ko threat and reply, and W4 recaptures at white+square. Then B5 is acceptable to Black in most cases: W6 seems required locally, and this exchange gains Black influence.

Outside contact ladder line  

B1 and B3 to capture white+circle in a ladder aren't seen so much, now. After that Black's ladder capture at b, and attempt to force White at a, are important follow-up plays.

See further discussion at Capture the cutting stones in joseki 1.

[1] W2 at B3 is known (Hashimoto Utaro) but in a context where B1 related to a ladder question. W2 at the square-marked point, playing into bad shape (see six kyu noseki) has been played by Sakata. B3 at W4 is known in a game of Go Seigen, and as played by Cho Tae-hyeon.


But then, how would you answer to Cho Tae-hyeon's variation? I've thought about this a lot and haven't come up with any good sequence for white.

xela: The key point is a, by analogy with a well-known joseki. Black will reply at b, then white can play c to make life in the corner. White can also force at d before playing c, expecting black e, but black can reply at f instead to make things more interesting :-)

(Why is c the correct shape to make life? There must be some interesting variations behind that choice, but I don't know, I'm just copying what I see in pro games... Perhaps white x instead allows black to seal white in with sente?)

Minue: A brief answer to xela's Question.

Which one is better for black of 2 follow ups below?

The answer is obviously the second one. So, white chooses the first follow up, so it's joseki sequence.

Follow up 1)  
Follow up 2)  

Question follow-up: But according to this Six Kyu Noseki, black could set up a double-hane like this, if white plays as xela suggested:

double hane  

And then there's no good continuation for white?

4-5 point 4-3 approach outside contact last edited by on January 27, 2015 - 05:49
RecentChanges · StartingPoints · About
Edit page ·Search · Related · Page info · Latest diff
[Welcome to Sensei's Library!]
Search position
Page history
Latest page diff
Partner sites:
Go Teaching Ladder
Login / Prefs
Sensei's Library