# Three-space extension

Difficulty: Beginner   Keywords: Opening

Chinese 1: 拆三 (chāi sān)
Chinese 2: 三间拆 (sān jiān chāi)
Japanese: 三間ビラキ (sangen biraki)
Korean: -

Three-space extension on the third line

is the three-space extension along the third line, like other extensions a big fuseki point which creates a base for the group and prevents White from attacking around the same point. Compared with the two-space extension, the three-space extension develops more quickly, but has the obvious defect at a where White can invade. This is always a consideration when making the three-space extension.

Three-space extension on the fourth line

It is also possible to make the three-space extension on the fourth line.

Mixed three-space extension

This three-space extension could also be called a very large knight's move extension.

Three-space extension from a wall

Here, Black makes a three-space extension from a wall.

Completing the shape

Black can follow-up with here to make a robust shape.

Developing with a one-point jump

, a one-point jump, is another alternative for developing from the three-space extension.

Perfect shape

If for whatever reason White plays the diagonal attachment at , Black's marked stone ends up ideally placed after the stand of (see extension from a wall). One line closer at a would be over-concentrated, that is, worse, from the point of view of good development.

Treating one stone lightly

Depending on the situation, Black may also choose to treat one of the stones in the formation lightly for the sake of development.[1] This type of sequence might be appropriate if White is strong in the upper right, as here. In that case Black a, White b might be good for White, and Black is better allowing in return for .

Variation

If instead , gives Black a wall and nice shape.

[1]

Approaching strong stones

Bill: In this particular situation, is problematic because it approaches White's wall, while extending only to a instead of allows White to play at b.

Prepare the way

Bill: To avoid the problems of an immediate extension, - press against , preparing for a safe extension to .

Charles This idea of Bill's, to use the 3-5 point low approach, press, is a bit more subtle than may seem at first glance. For example, is held back one line, giving White much less chance of fighting on this side.

Three-space extension last edited by Unkx80 on August 16, 2008 - 23:45