Referenced by ( 2022MainLine)

: ( 2038)
Black descends to the lower edge, securing his territory in the lower left corner.

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White pushes at the upper edge in return, reducing Black's territory there.

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Giving atari from the inside is a tesuji here.

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White's connection is an atari at Black's two stones again.

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White loses two tempi in the Main Semeai, but gains an additional four points of territory for a net gain of two points.

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Black captures White's single stone in the right centre for a net gain of two points, as had been explained above.

becomes an additional approach-move liberty for his large group.

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White captures Black's two stones in the upper right.

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Black has to recapture.

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White's attachment in the centre of three Black stones aims at exploiting Black's weakness of his cutting point below.

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Black's wedge is a tesuji that is not necessary here.

Alternatively, Black might connect at immediately.

Black's tesuji finds its application in cases where White has captured his stone , which massively weakens Black's eye shape in the lower left corner.
In some circumstances the corner is only enough for one eye, so Black has to secure another one in the left centre.

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Black's first connection.

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Black's second connection secures an eye above.

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The game continues on a well-known path.

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Black plays 1/1 reduction.

After her decision point, White will connect at .

Capture Variation:

Compared to the superordinate variation, ...

• Black's cumulated loss in the upper left corner is four points.
• Black's cumulated loss at the top is five points.
• White captured one Black stone in the left centre, so gaining one point.
• Black destroyed one point of White's territory in the upper right corner.
• Black's cumulated gain in the right centre is three points.
• Black's got an additional point of territory in the left centre.
• Black's cumulated gain in the lower left corner is five points.

In total, gains and losses compensate for each other.

White + 2 => White + 2

Semeai Variation:

Compared to the superordinate variation, ...

• Black's cumulated loss in the upper left corner is four points.
• Black's cumulated loss at the top is five points.
• White captured one Black stone in the left centre, so gaining one point.
• In the upper right corner, White captured two Black stone more, so gaining two points.
• In the left centre, Black captured one White stone less, so losing one point.
• Black's cumulated gain in the lower left corner is five points.

In total, Black lost eight points.

Black + 6 => White + 2

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