Tsuke-osae
Keywords: Joseki, Shape
This sort of pattern: is a contact play (tsuke) and
a block (osae). This is a territorial way to play.
![[Diagram]](../../diagrams/9/683d7d36bdb2103c25e2dcf963f723fa.png)
Empty triangle versus cutting points
White normally plays immediately to give Black an empty triangle. Then White has to deal somehow with the two cutting points a and b. Neither side has perfect shape here, therefore.
Before is played, there was some aji at c - which disappears after
. Black can play attach-block as an attacking technique, to make White heavy. When White is defending a group, the atari play
is probably something that White must play.
See attach-block joseki.