4463 enclosure 2-4 approach

  Difficulty: Expert   Keywords: MiddleGame, Joseki
[Diagram]
Hem approach  

This low approach to the 4463 enclosure has been popular recently, in particular with Korean players. Some new variations have emerged.

The 'hem' name comes from the Japanese, and comments on the way W1 is on the edge of the open skirt. (See also submarine.)

[Diagram]
Black's replies  

Black has a wide range of replies, since White is not forcing play in any one direction. The answers from a to e are given in order of apparent popularity in pro games. Answer f is an innovation popularized by AI.


[Diagram]
Thrust  

If Black thrusts down at B1, White almost invariably extends to the outside with W2, followed by B3. W4 next forces Black to choose, and thus can be regarded as a probe: Black will either answer at B5, allowing White to connect under at a in the endgame, or at a, giving White some aji in the corner. Either way, White will leave W4 alone for the time being and extend to W6 or some such point (the exact position depending on the place and colour of stones further down the left side).

Note that W4 is played more often than not in this position by professionals, but can make White's stones a bit heavier, and give up some aji in the corner. See [ext] http://lifein19x19.com/forum/viewtopic.php?p=84568#p84568.

[Diagram]
Three-three  

B1 is a quiet move. White has not much to do in the corner, and extends along the left side. Again the exact extension depends on the further left-side position.

[Diagram]
Cave in  

With B1, Black tries to confine White to the corner. White follows orders with W2 and W4. After B7, White usually plays elsewhere. So a is left as a very large point for both sides - note that when Black plays a, the best White can get in this corner is a ko.

[Diagram]
Escaping the enclosure  

If White does not want to be locked into the corner as shown above, she can walk out with W4 here, although she does run the risk that her resulting group becomes weak. After B7, White plays a or b to move out.

[Diagram]
Keima  

The keima at B1 is of all Black's choices the one that's most determined to take the outside and give White the corner. Usually this will succeed, this diagram giving a typical variation.

For the play at e, see 4463 enclosure second-line diagonal attachment.


Programs like LeelaZero suggest a faster response, the Ogeima

[Diagram]
The AI mainline  
[Diagram]
The AI sideline  


4463 enclosure 2-4 approach last edited by VanMorrison on September 13, 2018 - 16:56
RecentChanges · StartingPoints · About
Edit page ·Search · Related · Page info · Latest diff
[Welcome to Sensei's Library!]
RecentChanges
StartingPoints
About
RandomPage
Search position
Page history
Latest page diff
Partner sites:
Go Teaching Ladder
Goproblems.com
Login / Prefs
Tools
Sensei's Library