:
In the professional solutions, Black must throw-in to reduce White's liberties. A further analysis of this first throw-in can be found later ( 917).

:
Until Cheng Xiaoliu 6p used this move in 2010 [LIT. 9], it was played immediately at , White answered at . A discussion on this topic starts later ( 914).

(Referenced by 754)

, :
In the solution of Fujisawa Hideyuki 9p, with / already there, the exchange of / was not played ([LIT. 1; page 242]).

If the second throw-in (; was at / was at ) is not played, then the stone is not present on the board, and a move at 23 is double-sente, so it must be played at the earliest possible moment. If Black lets White get this point, he loses two points in the Semeai Variation.

Here, with the second throw-in, White is gote, and there will be no gain of two points for White. On the other hand, Black loses a ko-threat by playing at now. For the sake of better comparison, we kept these two moves in the historical order, introduced by Cheng in 1988 [LIT. 3; page 355], for the professional solution.

(Referenced by 45; 198)

: (A 432)
We have shown that, if Black plays guzumi at instead (technically best after some forcing moves in the top right corner), he wins. This guzumi has not yet been discussed by professionals.

: (A 725; B 728)
White must live on the lower side. White will neither win the semeai that starts with a move at , nor that begins with a move at . We present these variations in detail, to make clear that there is no difference between our solution and the classical line, regarding the outcome of the various semeai.

: (A 221; B 219; 79 363)
This is the latest of all moments that Black could successfully play the guzumi at , according to our estimation.

As shown in the variation for in our solution ( 555), Black cannot prevent White's large endgame in the upper left, with a move at , later. So what about giving this move a try, just before the Crosscut Sequence is completed? However, despite all efforts, Black will not win.
It will also become very complicated if Black captures White's left side with a move at . And again, Black will not be successful.

: (A 224)
The window of opportunity for the guzumi is closed now.

Please note that the link directs to a subvariaton of Our Solution, showing a position that is similar to this one here.

:
This is the first genuine gote move.

(Referenced by 505)

: (A 730)
We will see soon that White could pre-empt potential technical difficulties from the very beginning if she played this move at , instead.

: ( B 730a; C 730d)
:
However, as we now know, White must start the endgame on the left side "early" by playing the "classical" atari at .
According to our analysis, this is her only option to keep Black from playing the kikashi of Michael Redmond later, mentioned below ( 718), that would lose her the game.

Quite the contrary, choosing the tsuke of Yamada Shinji 6p, instead, will not lead to success.

:
There is no need to play this atari immediately. To prevent the complication of a "late" guzumi, it should be technically correct for White to play at , at least no later than this. White could have done this as early as move (= ), with which she captured the nine-stone nakade.
Additionally, it seems to us that it would later be technically better for White, not to give atari at , but to play at , instead. demonstrably works completely independent of the rest of the board ( 822), while - in principle - the success of the atari at depends on ko (assuming that the liberty count is not an issue, but what is not the case here).

: ( B 730a)
:
However, as we now know, White should not miss her second opportunity to start the endgame on the left side "early" by playing the "classical" atari at .
According to our analysis, this is her only option to keep Black from playing the kikashi of Michael Redmond later, mentioned below ( 718), that would lose her the game.

Please note that the link directs to a subvariaton at an earlier moment of this Professional Solution, as the now more advanced Nakade Sequence does not affect the rest of the board.

(Referenced by 508)

: (94 731)
It is very likely that it is now too late to play the guzumi at , instead.

:
White is reduced to only one eye at the left, so she has to keep Black from occupying the guzumi point.

: ( A 730a)
:
However, as we now know, White must not miss her third, and last, opportunity to start the endgame on the left side "early" by playing the "classical" atari at .
According to our analysis, this is her only option to keep Black from playing the kikashi of Michael Redmond later, mentioned below ( 718), that would lose her the game.

Please note that the link directs to a subvariaton at an earlier moment of this Professional Solution, as the now terminated Nakade Sequence does not affect the rest of the board.

:
Black starts the reduction of White's upper right corner, destroying two points of territory.

(A 737a):
White blocks.

White would like to retreat with a move at , instead, in order to frustrate Black's intention to utilize the hasami-tsuke/kikashi combination mentioned below.
However, she will be unable to succeed, due to the unfinished endgame position in the upper left corner.

(98 738), :
Each move reduces White's territory by another two points.

In principle, Black could also play hasami-tsuke at with , the final score would remain unaffected.

(Referenced by 717)

:
, , :
The combination of Harry's hasami-tsuke (, ) and the kikashi in the bamboo joint () of Michael Redmond will enforce a Black win by two points, according to our amateurish analysis.
Yamada Shinji's tsuke will not be possible for White any longer, and keeping with the "classical" atari , as in this main line of the Professional Solution, will be better for her, but neither lead to success.
This will be shown in detail in the subvariation for ( 738).

: (102 742)
Black cannot continue in the top right corner.

(Referenced by 509)

:
This starts a technically incorrect order of moves to fill the nakade, according to Ōhashi Hirofumi 6p ( 820). However, here with the classical sequences, and its variations, we kept the original order of moves.

(Referenced by 744)

: (A 745)

White captures Black's centre group now. For a long time, this move has been assessed to be disadvantageous for White. Instead, White continued at , and eventually captured - in the Semeai Variation - Black's top right group instead of the one in the centre.

(B 749)
If White wanted to play the complete endgame on the left side, beginning with the tsuke at , found by Yamada Shinji, before capturing Black's centre, she is a bit too late now - Black can resist more vigorously.

:
Black recaptures.

:
White must play this oki. Continuing the semeai at top right, with , for example, instead loses four points. This is shown in the variation for in the Capture Variation of our solution ( 585).
This oki - for a long period of time overlooked by professionals - was rediscovered by Joachim Meinhardt, and is the death blow to the classical solutions.

: (139 751)
:
The tsuke of Yamada Shinji would be possible now, because White's group on the left is definitely alive. Compared to this solution, there would be an advantage of two points for White overall, and she would thus win the game by this margin.

: (152 752)
Black should not connect the atari with a move at now. He will lose sente, and eventually one point.

:
Even if White plays one point higher at , Black still cannot later get an additional point of territory in the centre here, as shown above ( 567). This is because White ends in sente on the right side and could play at with , for example.

:
Black takes the last valuable point. This is the second additional point lost by the failure to play the tsuke of Yamada Shinji. Cheng's solution ends here.

:
We have added the moves from to .

(Referenced by 223)

The published professional solution ends in a draw (jigo) only.