Atekomi

Atekomi  

So here is atekomi (literally meaning "hit inside"). There are typically supporting stones nearby.

In English atekomi has also been called an angle wedge play. With a supporting stone at a Jared proposed the name Kosumi Cut, because the cutting stone is a kosumi and because it cuts opponent's kosumi.

There are some cases where atekomi is a hard-to-find tesuji. White can simply connect as an answer, so the tesuji usually has other aims in addition to separating the two stones, as in the examples below.

Example 1

Tesuji  

is atekomi. Black can't protect at both a and b.

This particular example happens to be a Clamping Tesuji as well, however, this would still be atekomi even if the marked clamping stone wasn't there.

Example 2

Connection  

The atekomi, , connects underneath.

Example 3

Black to play and kill  

The atekomi, , sets up the eye killing play, .

Real game example

(This example comes from KGS - exam vs. pyczhm 7-2-05)

Atekomi  

Black has just played and now white must try to escape. Perhaps white thought 'a' might work, but it does not.

Atekomi  

After , White is cut.

at 'a' or 'b' would fail; the Kosumi Cut works where other cuts do not.

'a' or 'b' is a common mistake because we are used to StrikeAtTheWaistOfTheKeima