: ( 648go)
White's wedge at is also possible here.

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White loses her just played stone.

Please note that White's group at the left still has a liberty at lA.

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Please be aware that Black has to connect after White's atari.

Otherwise, it will develop a ko fight that Black cannot win.

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White uses her sacrifice at the left to play this large move at the right.

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Black continues with the Main Semeai, giving atari at White's two stones in the lower left.

It is too early to play the kikashi of at the top; please refer to ( 648ap) for details.

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White connects.

White is better in the Capture Variation than in the Semeai Variation, therefore she will not choose Dany's Sacrifice here.

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Now, the time is ripe for Black's push at the top.

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Black captures White's single stone at the upper edge.

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White blocks at the upper edge.

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Black connects at the upper edge.

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White continues with the Main Semeai.

Black plays 1/1 reduction.

Capture Variation:

Compared to the superordinate variation ...

• Black captured an additional White stone in the left centre, so gaining one point.
• Black reduced White's territory in the upper right corner by one point.
• White gains two points by capturing Black's single stone in the lower right.

In total, gains and losses compensate for each other.

White + 2 => White + 2

Semeai Variation:

Compared to the superordinate variation ...

• Black captured an additional White stone in the left centre, so gaining one point.
• White captured an additional Black stone in the upper right, so gaining one point.
• In the lower right, White captured one Black stone less, so losing two points.
• In the left centre, Black did not capture one of White's stones, so losing two points.

In total, gains and losses compensate for each other.

Black + 4 => Black + 4