: ( 648qc)
Black connects in the upper right.

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White pushes from above.

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Black blocks immediately, simplifying the matter.

It does not make sense for Black to continue with the ko fight with re-capturing at , because White is ahead in viable ko threats.

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White connects the ko - sooner or later.

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The Main Semeai continues.

Black plays 3/4 reductions.

If he played 4/4 reductions, the scores of the Main Variations would be interchanged.

Before the end of the game, Black will have to capture at in the lower left corner.

Capture Variation:

Compared to the superordinate variation ...

• White got an additional two points of territory at the top.
• White did not capture Black's stone in the lower right, so losing two points.

In total, gains and losses compensate for each other.

White + 2 => White + 2

Semeai Variation:

Compared to the superordinate variation ...

• White captured two Black stones less at the top, so losing three points.
• White captured one Black stone more in the lower right, so gaining two points.

In total, Black gained one point.

White + 2 => White + 1