A snapback (Japanese: utte-gaeshi or utte-gae) is a play which captures enemy stones using one or more sacrifice stones.
Table of contents | Table of diagrams A snapback If Black captures A common joseki Black's escape Black is captured |
in the diagram captures the two
stones in a snapback.
This means that Black can capture the white stone just played with , but it puts the group into atari. Thus White can capture the stones by playing at a next.
So, above effectively captures the two
stones in a snapback although
itself can be captured.
Black should not want to play (no point improving White's liberties and eye shape); but it can be used as ko threat.
It is possible to set up a snapback of two stones, like in this diagram. =) --unkx80
Threatening to capture stones in a snapback is an effective tesuji, as in this joseki:
This diagram shows the result of a common joseki (for the 4473 enclosure) where White invaded at the 3-3 point under Black's 4-4 point. Usually this joseki ends with Black playing where White's marked stone is. But if taking sente has priority it is not uncommon to omit this move.[1]
So in this diagram White played at this point. If Black now plays around a or extends along the upper side Black is in for a nasty surprise: White plays . This threatens a snapback at 2 and is tesuji. In order to avoid losing stones to capture, Black plays
. But White follows with
and captures the whole group. There is no way out for Black (Black b is answered by White c).
-- Arno Hollosi
The snapback is one of the first tesujis aspiring Go players learn and employ with satisfaction.
(Arno Hollosi)
A snapback could be seen as a basic kind of under the stones play. -- Doug Ridgway
There is a tesuji for black to escape.
at
does not work either.
Arno: I am pretty confident that the black stones are captured after this sequence.
See also:
[1]
Bill: Do the pros commonly tenuki to take sente in that position? Is that really joseki?