[Welcome to Sensei's Library!]

StartingPoints
ReferenceSection
About


Paths
ThreeSpaceExtensi...

Referenced by
ShoulderInvasionO...

 

Attachment invasion of mixed three space extension
Path: ThreeSpaceExtensionInvasions   · Prev: LowInvasionOfMixedThreeSpaceExtension   · Next: ShoulderInvasionOfMixedThreeSpaceExtension
  Difficulty: Advanced   Keywords: MiddleGame, Joseki

[Diagram]
Invasion

Please elaborate.

Charles This is one of the (two) standard invasion points.



(DaveSigaty: I can't fully agree. This move needs to be put in context [2])
Charles Someone else referred to Attack and Defense - the book, re another variation for this shape - and that calls this a reduction. Well, maybe it is: and maybe it can turn into a kikashi sequence too. In other writing I have used 'invasion point' as a term for vital point in loose extensions.

[Diagram]
Invasion

Any of a to d is a possible answer by Black: all we can be sure is that Black should react directly to WC.


[Diagram]
Staircase

The most common way is B1, and then White really must play for a staircase at W2. Now Black might connect solidly, or play atari allowing White to set up a ladder. White ought to check the ladder before playing the attachment.


[Diagram]
Staircase: connection

If B1, it is expected[1] that White plays W2 to try for a sabaki result here: White could indeed connect at p, too, but that may be too heavy in practical play.


[Diagram]
Staircase: ladder

Given a good ladder, White should be happy up to W6. Otherwise White should play W4 as kikashi and look to create a good ladder by fighting.


[Diagram]
Staircase: descent

The low play B1 here has been played by some very strong players, recently. It looks submissive, and White may not feel inclined to continue here.

It was played in a title match O Rissei-Yoda Norimoto (B)1996-04-04 (colours reversed) Later White played down with a as a kind of inducing move: after Black b, White c, Black d White had stones in the centre and a serious cut at x to target.



[1]

Well, this happens anyway in the typical case:

[Diagram]
Side formation


[2]

[Diagram]
Side formation 1

Here W1 is the typical move. Other frequent plays are a and b. The attachment at c is not common.


[Diagram]
Side formation 2

When the stone on the left is high, the critical area is still on the right. W1 remains by far the most common play. Now however, the idea of pressing down with b or c is more common than the invasion at d. The attachment at e remains rare.

Yi Chu-yong (W) - Cho Hun-hyeon, 26th Wangwi League?, 1991-07-26

[Diagram]

The invasion starting with W1 is seen when Black's position after B4 will be overconcentrated. This is one typical case.


[Diagram]

The game continued like this. Notice that Black has played a total of 8 stones in the lower left side, capturing just 3 White stones.



Yi Ch'ang-ho (W) - Cho Hun-hyeon, 35th P'aewang, 2001-01-12

[Diagram]

In this example Black responds aggressively with the cut at B4. Play continues naturally until B10 which attempts to break the ladder on the lower side...


[Diagram]

B10 recaptures the ko

When White responds with W1 the right side transposes into the second example of the attachment invasion in this game. With W3 White repeats the cut that Black played on the lower side.



Path: ThreeSpaceExtensionInvasions   · Prev: LowInvasionOfMixedThreeSpaceExtension   · Next: ShoulderInvasionOfMixedThreeSpaceExtension
This is a copy of the living page "Attachment invasion of mixed three space extension" at Sensei's Library.
(OC) 2003 the Authors, published under the OpenContent License V1.0.