( 978)

(Referenced by 163; 251; 992)

White did not play the gote move at , but at . Thereafter, the exchange of / is sente for White. The Punishment Semeai Liberty Level is "six" now, so White has captured the ko a bit "early" here (related to the Main Semeai). However, with Joachim's Ko-Semeai, it seems suitable for White to start the ko, when her centre group is reduced to five liberties.

Black has one ko-threat in the hanezeki, at , but which is suicidal here, and so can be utilized "late" only.

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Again, Black needs one external ko-threat, and he may play it just now.

Please note that there are no valid ko-threats in the nakade, despite Black has not connected the hanezeki's tail yet. Black will need two moves in a row to decide the situation on the left side in his favour. But in the meantime, his top right group will get below the Punishment Semeai Liberty Level.

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has reduced Black's liberties to the Punishment Semeai Liberty Level, so Black must connect the hanezeki's tail with .

Ko: ;

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on the upper edge is a valid ko-threat here, because White's group has only three liberties left.

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We assume that White does not have any valid ko-threat.

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Black wins the ko-fight.

With the double throw-in, we can conclude that the number of exceeding Black ko-threats (over White ones) to win the ko-fight is one.

This is independent from what has happened in the upper part of the hanezeki, if White captured the ko at the moment, when her centre group is reduced to five liberties.

Ko: ;

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Please be aware of the false conclusion to assume - e.g. on the basis of the position after - that White needed two ko-threats to win the ko-fight, i.e. one more than Black, due to Black's suicidal ko-threat in the hanezeki.

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Black is unable to give atari at , so White wins the semeai.

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However, as a matter of course White would have utilized her ko-threat much earlier. To simplify the matter, White will choose a moment after Black has connected the hanezeki's tail.

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We here assume that - alike the main line of Joachim's Ko-Semeai - Black does not have more ko-threats than White. On the right side of the board, there is this suicidal ko-threat for Black only.

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Due to Black's suicidal move, White wins the semeai with Black's connected group on the lower edge.

Using the gote-sente-combination of , , and , in the hanezeki does not really make a difference.