: ( 648qc)
Black throws-in in the guzumi area at the right.

Please note that this move loses one point in both Main Variations, and additionally one tempo in the Main Semeai.

:
White has to capture or course, stopping Black from living independently at the right.

:
Black recaptures the ko.

:
White lets Black have what he wanted, and connects her stone in the right centre.

After Black sacrificed one stone in the guzumi area, it is no longer desirable for White to win the ko in the left corner.
If she used the atari at in the lower left corner, in order to do so, she would revert to the scores of the superordinate variation. Both sides would have played a disadvantageous ko threat at the very end of the ko fight, at the cost of one point each.

:
Black connects the ko.

Black must not play any reduction.

Capture Variation:

Compared to the superordinate variation ...

• Black's cumulated gain in the left centre is two points.
• Black's cumulated gain in the lower left corner is one point.
• Black captured an additional White stone in the guzumi area.
• White connected her stone in the upper right, so gaining three points.

In total, Black lost one point.

White + 2 => White + 3

Semeai Variation:

Compared to the superordinate variation ...

• Black's cumulated gain in the left centre is two points.
• Black's cumulated gain in the lower left corner is one point.
• Black captured an additional White stone in the guzumi area.
• White captured one Black stone less in the upper right, so losing two points.
• White gained one point of territory in the upper right corner.

In total, Black gained three points.

White + 2 => Black + 1