4-4 point low approach, tsukenobi, jump attachment

Variants  

See the appropriate section below for

the wedge at a (was common, now considered to favour White),

the hane at b or

the cut at c (requires a ladder).

Table of contents Wedge Hane Cut

Wedge

[10] The jump in  

to is a common continuation, though Leela Zero suggests it may be better for White and Son Geungi 4p says it (or the continuation in the next diagram) is not seen this sequence in pro games, for a good reason.

Black builds influence  

After , is the most common answer, but tenuki and White at have also been played. If White does not play , capturing there is a big point for Black as well. is a key point for influence, and should not be omitted.

White cuts  

Although the joseki has ended with in the previous diagram (or if there is already a black extension on the left side), White is left with the large move of . The difference between White playing here and Black playing a is 22 points. Still, it is only points, and thus considered large yose.

Black's countermeasure (8 connects)  

On the other hand, White should not wait too long to play in the previous diagram either. If Black's position along the left side is more solid, he could play at here, and try to kill the white stones. If White feels unable to resist this variant, her endgame move is at in this diagram.

The other atari  

This variant I found in Jan van der Steen's database and has apparently been played between professionals.

Unfortunately, I do not know what Black would have played, had White run out with instead of .

Comment: I don't think White would actually respond in the way shown. It seems to me that is a suicidal move.

Bill: I suspect that is a typo for a play at .

A variation?  

Charles This was played in 1859 by Ebizawa Kenzo against Shusaku, deep in the middle game (around move 100). Looking at the context in that game (the only example in the Gogod database), it seems clear that would have been played only as a sacrifice to take sente for some large-scale play like the circle or square points. It makes no sense, really, as a joseki play relative to the corner.

Hane  

Black's second choice after is the hane at . and form a very simple variation, after which both players extend with and . could also be played at a, and many other possibilities exist for .

Hane  

is the other option in this variation. Black should not omit ; this is a key point for both players’ eye shape. After White extends to , Black defends at .

Charles Matthews There are not many pro games in which is played, it seems. But the variations there are rather different: at omitting the atari, or at a. I wonder if this line to is more like a ‘handicap game joseki’.^[1] In even games White is also interested in pushing up to b.

Sacrifice  

White tries to start up a fight with and , but Black sacrifices the corner in exchange for extra influence.

Continuation  

Although White has taken the corner, her territory is surprisingly small – only 15 points or so (White will have to take the black stones off the board). Black’s thickness is much more valuable.

White cuts  

If White cuts with first, Ishida’s book gives this variation.

Continuation  

White manages to capture some black stones, but Black gets a nice amount of territory, and can look forward to a ladder block as well. Of course if the ladder does not work, this variation is even more problematic for White.

Cut  

tderz: Black tries this violent cut.
What are White’s good replies?
What is the difference if around is , or empty?

 

tderz: the game above went on like this:
is meant to create some confusion, as Black will have more choices to capture/control the cutting stones +.
is a serious mistake (atari) as it only helps White to get more levy on the right black stones.
Only would have done the same job without helping White.
looks like tesuji to me – at least it’s fun and worth the experimenting.

 

tderz: : Blocking at Bp5 here had some really interesting variations, which were feasible for Black.
White survived and is not confined and out with = and has split.
The result is certainly not bad for White.

 

tderz: There exists a tesuji which prevents the ladder
(=Bp5) =Wq5 (threatening white's ladder Wo6)
=Bs5! =Ws6 (threatens ladder again)
=Br6! =Wq6
=Bq7! .... (White was always forced and Black would have avoided the ladder in sente.

If White then wanted to live in the corner, another ladder could appear on the outside ...
and White had been lost.

 

tderz: might be useful in the later fight

 

tderz: Black should die or lose his middle stones if he pulls back with =a.

 

tderz: With , White had to be sure to win the semeai (against the center group), if Black choses the option --,
as it denies White the option to live independently, while Black is alive.

Unlikely Black response  

Somebody: How about just taking the corner in this fashion?

Going for left side  

Somebody: Another option for Black, but White has some territory, can get out and the marked Black stone is placed suboptimally. White a next seems like a big move, as b is sente followup whereas Black b becomes sente only much later in the game.
tderz White a is a big gote move at this stage, at best forestalling (reverse sente]; preventing) black a which threatens really big black c (also limiting to one eye).

Going for left side  

(2, 7 elsewhere)

Somebody: The marked stone is a bit too close, but if it's played further away White may play otherwise.
tderz: Black got a sente move

Likely result  

Somebody: White got corner profit in sente.