: ( 648ay)
White plays the wedge in the left centre.

:
Black gives atari at White's just played stone.

; :
White forces twice.

:
Black captures.

: (131 648bm)
White extends, intending to create two points of territory in the left centre.

It might be tempting to cut Black's troupes apart by cutting with , but White would lose one point overall.

:
Black captures White's single stone at the upper edge, gaining two points in return.

:
White blocks at the upper edge.

:
Black gives atari at White two stones in the lower left.

:
White continues with the Main Semeai, choosing Dany's Sacrifice.
Black is comfortably ahead in the Capture Variation, so White does not want to connect her two stones.

Please also note that she does not want to capture with at the upper edge, just because she would be unable to connect thereafter. Losing another Main Semeai Liberty would be fatal in the Semeai Variation.

:
Eventually, Black connects the ko at the upper edge.

Black plays 0/1 reductions.

Capture Variation:

Compared to the superordinate variation ...

• Black's cumulated gain at the upper edge is two points.
• Black captured one White stone in the left centre, but lost one point of territory there, so the net effect is zero.
• White got an additional two points of territory in the left centre.

In total, gains and losses compensate for each other.

Black + 4 => Black + 4

Semeai Variation:

Compared to the superordinate variation ...

• Black's cumulated gain at the upper edge is two points.
• Black captured one White stone in the left centre, but lost one point of territory there, so the net effect is zero.
• White got an additional two points of territory in the left centre.

In total, gains and losses compensate for each other.

White + 2 => White + 2