: ( 648eb)
White connects her single stone at the upper edge.

Ko:

:
Black is forced to recapture the ko first.

He is unable to terminate the ko fight just now.
If he played any of his kikashi or , he would enable White to also use one of her potential ko threats without affecting the outcome of the ko fight. White would insert her kikashi at in the lower left corner, gaining one point overall unnecessarily.
Immediately defending his lower left corner with is also out of the question. White would gain one point overall by blocking at .

:
Black plays his push at the top, but does not necessarily intend to continue with the ko fight in the left centre.

:
White is forced to block immediately.

If she inserted her own kikashi in the lower left corner, instead, she would have erased one decisive ko threat unnecessarily (). Black would win the ko fight, and the Semeai Variation.

:
Now, Black is able to defend his loser left corner.

He might consider continuing with the ko fight for a while, using both of his kikashi in the hanezeki as a ko threat.

: (w 145 648en)
White continues with the Main Semeai, also erasing one of Black's potential ko threats.

As "usual" after the refutation of Dany's Sacrifice in the lower left, she does not really want to pre-empt Black's kikashi in the hanezeki by occupying the point of herself.

; :
Black plays his kikashi in the hanezeki.

:
Black continues with the Main Semeai.

:
White has to connect the ko - sooner or later.

Black plays 2/3 reductions.

Capture Variation:

Compared to the superordinate variation ...

• White's cumulated gain at the upper edge is two points.
• Black destroyed one point of White's territory at the top.
• Black's cumulated gain in the lower left corner is two points.
• Black did not destroy one point of White's territory in the upper right corner.

In total, gains and losses compensate for each other.

White + 1 => White + 1

Semeai Variation:

Compared to the superordinate variation ...

• White's cumulated gain at the upper edge is two points.
• Black destroyed one point of White's territory at the top.
• Black's cumulated gain in the lower left corner is two points.
• White captured one Black stone less in the upper right corner, so losing one point.
• Black captured one White stone less in the lower left corner, so losing two points.

In total, gains and losses compensate for each other.

White + 1 => White + 1