What a humiliating loss.
At move 52 (which took white like 3 minutes to come up with) I counted and I was ahead in liberties.
What a fool I was.

After that I played terribly.

If someone looks at the board at move 50 and say: white will win by 50 points. You'd say he knew nothing about Go and he should stop being silly.

Hi Ian,

This is a tricky one, it certainly looks at first glance like black should be fine and white is being unreasonable...

Firstly black should take the hane at the head of two rather than the decent, and the 2nd decent only reduces liberties on the black group too.

This is the best sequence I can see for black which looks to end up in a multi-stage ko or possibly seki (which white would be happy with...)

Click Here To Show Diagram Code

[go]$$W
$$ ------------------------+
$$ . . . . . . . . . . . . |
$$ . 0 9 . 3 2 4 . . . . . |
$$ . . 8 5 7 1 X . . O . . |
$$ . . X . 6 O X . X . O . |
$$ . . . . . X O O . . . . |
$$ . . . . . X . . . O . . |
$$ . . . . . . . O . . . . |
$$ . . . . . X . . . . . . |
$$ . . . . . . . . . . . . |[/go]

Click Here To Show Diagram Code

[go]$$Wm11
$$ ------------------------+
$$ . . . 5 . . . . . . . . |
$$ . X O . O X X . 6 . . . |
$$ . . X O O O X . . O . . |
$$ . . X 1 X O X . X . O . |
$$ . . . 2 3 X O O . . . . |
$$ . . . 4 . X . . . O . . |
$$ . . . . . . . O . . . . |
$$ . . . . . X . . . . . . |
$$ . . . . . . . . . . . . |[/go]

Hope that's useful

Possibly extending at the marked stone was an overplay and it should be at 'a' instead, that would definitely have killed the aji in the stone

Click Here To Show Diagram Code

[go]$$B
$$ ----------------------+
$$ . . . . . . . . . . . |
$$ . . . . . . . . . . . |
$$ . . . . . X . . O . . |
$$ . X . . O X . X . O . |
$$ . . . a X O O . . . . |
$$ . . . . Y . . . O . . |
$$ . . . . . . . . . . . |[/go]

Move 50? Actually, a properly cynical observer could see it coming at move 35.

This is the position at move 34. Black is building a moyo on the top side, and white is building one on the right side with his most recent move at Q10. As the proverb says, a move at the intersection of two moyos counts double.

Click Here To Show Diagram Code

[go]$$Wcm34
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . O O X . . . . . . . . . . . . . . |
$$ | . . O X . X . . . . . . . X . . O . . |
$$ | . . O X . . . . . X . . . . . X . O . |
$$ | . O X . . . . . . . . . . . . . . . . |
$$ | . O X . . . . . . . . . . ? ? . O . . |
$$ | . O X . . . . . . . . . . . . . . . . |
$$ | . . X . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . X . . . . . , . . . . . 1 . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . . . . . . . . . . . . O . . . . . |
$$ | . . . , . . . . . , . . X X X , O . . |
$$ | . . O . . . . . X . . . . X O O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

A move in the shaded area would enhance one moyo and reduce the other. ( Indeed, white probably should have played there himself with his last move - rather than Q10. )

Look at the board now if black gets to the crucial area first:

Click Here To Show Diagram Code

[go]$$Wcm34
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . O O X . . . . . . . . . . . . . . |
$$ | . . O X . X . . . . . . . X . . O . . |
$$ | . . O X . . . . . X . . . . . X . O . |
$$ | . O X . . . . . . . . . . . . . . . . |
$$ | . O X . . . . . . . . . . . 2 . O . . |
$$ | . O X . . . . . . . . . . . . . . . . |
$$ | . . X . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . X . . . . . , . . . . . 1 . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . . . . . . . . . . . . O . . . . . |
$$ | . . . , . . . . . , . . X X X , O . . |
$$ | . . O . . . . . X . . . . X O O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

Black's moyo is expanding, white's moyo is reduced, and the shoulder hit by white is now a very risky move.

Click Here To Show Diagram Code

[go]$$Wcm34
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . O O X . . . . . . . . . . . . . . |
$$ | . . O X . X . . . . . . . X . . O . . |
$$ | . . O X . . . . . X . . 3 4 . X . O . |
$$ | . O X . . . . . . . . . . 5 6 . . . . |
$$ | . O X . . . . . . . . . . . 2 . O . . |
$$ | . O X . . . . . . . . . . . . . . . . |
$$ | . . X . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . X . . . . . , . . . . . 1 . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . . . . . . . . . . . . O . . . . . |
$$ | . . . , . . . . . , . . X X X , O . . |
$$ | . . O . . . . . X . . . . X O O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

But in the game, black overplayed at O10:

Click Here To Show Diagram Code

[go]$$Wcm34
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . O O X . . . . . . . . . . . . . . |
$$ | . . O X . X . . . . . . . X . . O . . |
$$ | . . O X . . . . . X . . . . . X . O . |
$$ | . O X . . . . . . . . . . . . . . . . |
$$ | . O X . . . . . . . . . . . . . O . . |
$$ | . O X . . . . . . . . . . . . . . . . |
$$ | . . X . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . X . . . . . , . . . 2 . 1 . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . . . . . . . . . . . . O . . . . . |
$$ | . . . , . . . . . , . . X X X , O . . |
$$ | . . O . . . . . X . . . . X O O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------
$$ {AR Q14 O14}[/go]

...leaving a huge gap which white exploited.

_________________
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Thanks both for your input. Both are actually quite helpful. How one move can change the course of the game, it's amazing.