Invasion Defense

For lessons, as well as threads about specific moves, and anything else worth studying.
Post Reply
Ellisdee
Beginner
Posts: 3
Joined: Wed May 19, 2010 6:25 am
Rank: KGS 4k
GD Posts: 0
Has thanked: 1 time

Invasion Defense

Post by Ellisdee »

I've been seeing the following shape lately in games. I feel like I should be able to kill the group, although I also wouldn't be surprised if I can't. Trying to figure out what the best way to attack white in this situation is. In the game, I attached at S7, and chased the group out.

Click Here To Show Diagram Code
[go]$$Bc
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . X . O . O . X . . . X X O . |
$$ | . . . X . X . . . , . . . . X , O . . |
$$ | . X X . . . . . . . . . . . . . . O . |
$$ | . . O X . . . . . . . . . . . O . . . |
$$ | . . O X . . . . . . . . . . . . . . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . O . . O . 1 . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . O O . . . . . . . . . . . . . . |
$$ | . . O X X X . . . X . O . . . . O . . |
$$ | . . O , . . . . . , X X O O . O . . . |
$$ | . . X X . . . . . X . O X X O . . . . |
$$ | . . . . . . . . . . . X . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
User avatar
Solomon
Gosei
Posts: 1848
Joined: Tue Apr 20, 2010 9:21 pm
Rank: AGA 5d
GD Posts: 0
KGS: Capsule 4d
Tygem: 치킨까스 5d
Location: Bellevue, WA
Has thanked: 90 times
Been thanked: 835 times

Re: Invasion Defense

Post by Solomon »

The textbook, usually correct answer is the bump:
Click Here To Show Diagram Code
[go]$$Bc
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . X . O . O . X . . . X X O . |
$$ | . . . X . X . . . , . . . . X , O . . |
$$ | . X X . . . . . . . . . . . . . . O . |
$$ | . . O X . . . . . . . . . . . O . . . |
$$ | . . O X . . . . . . . . . . . . . . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . . . . a . |
$$ | . . . , . . . . . , . . O . . O 2 1 . |
$$ | . . . . . . . . . . . . . . . . . b . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . O O . . . . . . . . . . . . . . |
$$ | . . O X X X . . . X . O . . . . O . . |
$$ | . . O , . . . . . , X X O O . O . . . |
$$ | . . X X . . . . . X . O X X O . . . . |
$$ | . . . . . . . . . . . X . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

This forces a miai between 'a' and 'b'. If Black plays 'a', then 'b' by White ensures Black still doesn't have two eyes and almost cuts off R7. Black could save it with the clamp of S7 but it doesn't give Black additional eyespace and it saves in gote, so it's not a good choice. If Black plays 'b', then 'a' by White caps Black from creeping any higher up while also making sure Black doesn't have two eyes.
hanayeol
Beginner
Posts: 2
Joined: Sat Jul 10, 2010 8:48 am
Rank: KGS 4 dan
GD Posts: 0

Re: Invasion Defense

Post by hanayeol »

Ellisdee wrote:This move is vital point I think.
Click Here To Show Diagram Code
[go]$$Bc
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . X . O . O . X . . . X X O . |
$$ | . . . X . X . . . , . . . . X , O . . |
$$ | . X X . . . . . . . . . . . . . . O . |
$$ | . . O X . . . . . . . . . . . O . . . |
$$ | . . O X . . . . . . . . . . . . . . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . O . . O . 1 . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . O . . . . . . . . . . . . . . 2 . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . O O . . . . . . . . . . . . . . |
$$ | . . O X X X . . . X . O . . . . O . . |
$$ | . . O , . . . . . , X X O O . O . . . |
$$ | . . X X . . . . . X . O X X O . . . . |
$$ | . . . . . . . . . . . X . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
Post Reply