: ( 2043a)
Black occupies a Main Semeai Liberty of White's left-hand group, but does not significantly improve his shape in the upper left corner.
We inserted this move manually.

We will show below that he will be unable to resist strongly against KataGo's Immediate Crosscut after Yamada Shinji's Tsuke.

:
Yamada Shinji's Tsuke must be played latest now.

:
KataGo's Immediate Crosscut.

:
We inserted Black's (mistaken) atari from the outside manually here, for demonstrative purposes.

As a matter of course, the inside atari of would be correct for Black, reverting to the correct line of play that has been shown above.

:
White gives counter-atari.

:
Black captures White's pivotal stone.

:
White's atari at the top starts the rescue of her single stone in Black's corner.

:
White connects her five stones, making , , , , a real threat.

:
Black defends with this solid connection.

:
White continues the endgame in the lower left corner with the well-known hasami-tsuke there.

:
Black plays tenuki, in order to defend his upper left corner.

:
KataGo's surprising push inside Black's lower left corner.

:
Black is forced to defend with this calm move at the lower edge.

:
KataGo captures the nakade "early" here.

:
White's atari from the inside ...

:
... forces Black to capture.

:
White continues with spoiling Black's shape.

:
Finally, White captures Black's single stone to the right.

:
KataGo likes to insert this kikashi in the left centre, ...

:
... before taking profit outside the Main Semeai Area through this hane at the upper edge.

:
White played tenuki, so Black is able to generate one additional point of territory in the left centre in return, but which only partially compensates for his loss at the upper edge.

:
White's push into Black's lower left corner from the left does not lose a tempo in the Main Semeai, as an additional approach-move liberty is created.

:
White continues with the Main Semeai.

:
Black plays 0/1 reduction, in order to not increase White's score in the Semeai Variation.

:
Black has to take White's three stones off the board, before approaching White's left-hand group from the corner.

Before the end of the game, Black will have to connect at in the upper left corner, as well as at in the left centre.

Capture Variation:

Compared to the superordinate variation, ...

• White's cumulated gain in the upper left corner is one point.
• Black's cumulated gain at the top is four points.
• Black lost one point of territory in the upper left centre, but got an additional point of territory below, so the net effect is zero.
• White's cumulated gain in the lower left corner is seven points.

In total, Black lost four points.

Black + 2 => White + 2

Semeai Variation:

Compared to the superordinate variation, ...

• White's cumulated gain in the upper left corner is one point.
• Black's cumulated gain at the top is four points.
• Black lost one point of territory in the upper left centre, but got an additional point of territory below, so the net effect is zero.
• White's cumulated gain in the lower left corner is six points.
• Black capture one White stone more in the lower left corner, so gaining one point.

In total, Black lost two points.

Jigo => White + 2

2043a