Keywords: Shape, Go term

Chinese: 夹 (jia1)
Japanese: ハサミツケ  (hasami tsuke)
Korean: -

Black 1 is a Clamp  

When a friendly stone is already next to an enemy stone, a clamp is an attachment on the opposite side of that enemy stone.

Clamps can occur anywhere on the board at any stage of the game, as shown in the following examples.

The Japanese term for clamp, ハサミツケ  (hasami-tsuke), means literally "pincer attachment".

As can be seen in the example, the second line clamp is a common end-game tesuji. It makes a and b miai.

Types of clamps:

Moves 35 to 41  

This is Takagi Shoichi (Black) versus Kato Masao in the 43rd Honinbo League played in November 1987. Takagi uses it as the first example in section 2 of Beyond Forcing Moves.

When White plays at W2, Black continues at B3 and B5 in the knowledge that the clamp at B7 is available. However, the point of including it in his book is as an example of good forcing moves - by White! The clamp is effective in that White cannot prevent Black from connecting. However, Takagi did not really consider how well White could do by using a sacrifice strategy.

He may not have known that thirteen years earlier (December 1974) Sakata Eio had beaten Kato in the 30th Honinbo League with the same sacrifice in the same corner position. (Thank you GoGoD CD and Kombilo :-)

Moves 42 to 51  

White's turn at W3 yields a free forcing move in the corner at W5 before continuing with W7 and then stopping Black cold with W9.

Moves 52 to 54  

Finally White ends the play in the upper right in sente with W1 and turns to W3 to expand the upper left territory now backed up by White's new wall in the upper side.

This example demonstrates the basic clamp which can be a very powerful move. Indeed here it gives Black exactly what he wanted. Unfortunately he had not thought through the implications in this particular position well enough. As a result, the example is also a very good illustration of the resources at White's disposal. Black must have them in mind in choosing this type of clamp.

Moves 44 alternative  

Note that White can not win by turning at W3 after exchanging W1 for B2. B4, B6, and B8 make miai of a and b.


B1 here is a useful tesuji which technically qualifies as a clamp, but might better be called an attachment underneath.

Bill: Sakata, in Go no Tsume to Yose (Life and Death and Yose in Go), p. 166, calls this play a clamp (hasami-tsuke).


Here is another example from Segoe and Go Seigen's Tesuji Dictionary, Clamp problem 11.

These last 2 examples are both belly attachments. ~srn347

Clamp last edited by hnishy on May 27, 2018 - 03:57
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