Han Sanghoon, 8p - Lee Donghoon, 9p, White to play

Gomoto · Post by **Gomoto** » Fri Aug 02, 2019 8:23 am

White to play. Attack the black group in the lower middle for profit.

Click Here To Show Diagram Code: [go]$$Bc $$ --------------------------------------- $$ | . X . . . . . . . . . . . . . . . . . | $$ | O X . . . . X . . . . . . X . . . . . | $$ | . O X X X X . O . X O X O X . . . . . | $$ | . O O O X O O . O O . O O X . X . . . | $$ | . X O . O O . . . X O . X O . . X . . | $$ | X . X O X O . . . . . . X O . O O X . | $$ | . X O O . . . . . . . . X O X X . . . | $$ | . . . . . . . . . . . O X X O X X X . | $$ | . X . O . . X . . O . O X . O . O . . | $$ | . . X , . X . . O , X O O . O O X . . | $$ | . X O . X . . . . . X X . X O X O O . | $$ | . X X O . . . . . O X . X . O . O X . | $$ | . X O . . . . . . O O X . X O O X . X | $$ | . . . . . . . . . O X X X . O X X X . | $$ | X X X . . . . . . O X O O O O . . . . | $$ | X O O O . O O . . , X X O . O , X . . | $$ | O O . . . O X X . X X . X O X X . X . | $$ | . . . . . O O X . . . X O O O X O . . | $$ | . . . . . . . . . . . O . O . O . O . | $$ ---------------------------------------[/go]

Han Sanghoon, 8p - Lee Donghoon, 9p, B+R (Komi 6.5)
21st Nongshim Cup, Korean preliminary, 2019-07-26

Post by **Joaz Banbeck** » Fri Aug 02, 2019 12:04 pm

I'd play J4, which according to my reading, threatens the follow up at N9, after which the black group has only one solid eye at N7, and possible eye at the bottom that depends on black winning a ko.
This is not a pleasant ko for black, for white has an internal ko threat at O8, and large external threats at D9 then E11, and Q15.

Click Here To Show Diagram Code: [go]$$Wc $$ --------------------------------------- $$ | . X . . . . . . . . . . . . . . . . . | $$ | O X . . . . X . . . . . . X . . . . . | $$ | . O X X X X . O . X O X O X . . . . . | $$ | . O O O X O O . O O . O O X . X . . . | $$ | . X O . O O . . . X O . X O . C X . . | $$ | X . X O X O . . . . . . X O . O O X . | $$ | . X O O . . . . . . . . X O X X . . . | $$ | . . . . . . . . . . . O X X O X X X . | $$ | . X . O C . X . . O . O X . O . O . . | $$ | . . X , . X . . O , X O O . O O X . . | $$ | . X O C X . . . . . X X 3 X O X O O . | $$ | . X X O . . . . . O X . X C O . O X . | $$ | . X O . . . . . . O O X S X O O X . X | $$ | . . . . . . . . . O X X X . O X X X . | $$ | X X X . . . . . . O X O O O O . . . . | $$ | X O O O . O O . 1 , X X O . O , X . . | $$ | O O . . . O X X . X X . X O X X . X . | $$ | . . . . . O O X . . . X O O O X O . . | $$ | . . . . . . . . . . . O . O . O . O . | $$ ---------------------------------------[/go]

If black plays safe by taking N9 for himself and securing two eyes, white takes his profit in sente with F8 threatening E10.

Click Here To Show Diagram Code: [go]$$Wc $$ --------------------------------------- $$ | . X . . . . . . . . . . . . . . . . . | $$ | O X . . . . X . . . . . . X . . . . . | $$ | . O X X X X . O . X O X O X . . . . . | $$ | . O O O X O O . O O . O O X . X . . . | $$ | . X O . O O . . . X O . X O . . X . . | $$ | X . X O X O . . . . . . X O . O O X . | $$ | . X O O . . . . . . . . X O X X . . . | $$ | . . . . . . . . . . . O X X O X X X . | $$ | . X . O . . X . . O . O X . O . O . . | $$ | . . X , 5 X . . O , X O O . O O X . . | $$ | . X O . X . . . . . X X 2 X O X O O . | $$ | . X X O . 3 . . . O X . X . O . O X . | $$ | . X O . . . . . . O O X . X O O X . X | $$ | . . . . . . . . . O X X X . O X X X . | $$ | X X X . . . . . . O X O O O O . . . . | $$ | X O O O . O O . 1 , X X O . O , X . . | $$ | O O . . . O X X . X X . X O X X . X . | $$ | . . . . . O O X . . . X O O O X O . . | $$ | . . . . . . . . . . . O . O . O . O . | $$ ---------------------------------------[/go]

Assuming that black defends against that, white continues grabbing territory like this:

Click Here To Show Diagram Code: [go]$$Wc $$ --------------------------------------- $$ | . X . . . . . . . . . . . . . . . . . | $$ | O X . . . . X . . . . . . X . . . . . | $$ | . O X X X X . O . X O X O X . . . . . | $$ | . O O O X O O . O O . O O X . X . . . | $$ | . X O . O O . . . X O . X O . . X . . | $$ | X . X O X O . . . . . . X O . O O X . | $$ | . X O O . . . . . . . . X O X X . . . | $$ | . . . . . . . 5 . . . O X X O X X X . | $$ | . X . O . . X . . O . O X . O . O . . | $$ | . . X , . X . . O , X O O . O O X . . | $$ | . X O 4 X . . . . . X X 2 X O X O O . | $$ | . X X O . 3 . . . O X . X . O . O X . | $$ | . X O . . . . . . O O X . X O O X . X | $$ | . . . . . . . . . O X X X . O X X X . | $$ | X X X . . . . . . O X O O O O . . . . | $$ | X O O O . O O . 1 , X X O . O , X . . | $$ | O O . . . O X X . X X . X O X X . X . | $$ | . . . . . O O X . . . X O O O X O . . | $$ | . . . . . . . . . . . O . O . O . O . | $$ ---------------------------------------[/go]

Life In 19x19

Han Sanghoon, 8p - Lee Donghoon, 9p, White to play

Han Sanghoon, 8p - Lee Donghoon, 9p, White to play

Re: Han Sanghoon, 8p - Lee Donghoon, 9p, White to play