d4=. d16=. f17=40 k12=49 l9=48 l10=47 l11=43 l12=44 m9=50 m10=46 m11=42 m12=41 m13=45 n12=34 n13=37 n14=27 n15=35 n16=29 n17=31 n18=33 o12=38 o13=8 o14=25 o15=26 o16=28 o17=30 o18=32 p11=12 p12=10 p13=7 p14=4 p15=14 p16=15 p17=17 p18=36 q4=. q12=11 q13=3 q14=2 q15=13 q16=. q18=24 r8=39 r11=9 r12=21 r13=18 r14=1 r15=5 r16=6 s13=19 s14=20 s15=22 s16=16
Black 10 is usually played at 28 to make black strong, but here black plays 10 and 12 in Figure 1 to make a change. White 13 and 15 moves are a severe counterattack. If black 16 cuts as in Dia. 2, black should know enough to deal with white's variations to play move 2 first. One of the games between them proceeded in the way as shown in Dia. 2, the result shows that white is better locally.
d16=. k17=16 m14=15 n14=5 n15=6 n16=10 o13=. o14=11 o15=12 o16=7 o18=14 p11=. p12=. p13=. p14=. p15=. p16=. p17=8 p18=13 q12=. q13=. q14=. q15=. q16=. q18=9 r11=. r13=1 r14=. r15=. r16=. s13=4 s16=2 s17=3
10
White 25's cut and atari is an inevitable move. If this move is played as in Dia. 3, then black 2 will make a good shape. When white plays move 9 to avoid being attacked, black 10 is a good move. Apparently, it is disadvantageous for white.
n15=2 n17=10 o13=. p11=. p12=. p13=. p14=. p15=. p16=. p17=. p18=1 q12=. q13=. q14=. q15=. q16=. q17=5 q18=. q19=7 r8=9 r11=. r12=. r13=. r14=. r15=. r16=. r17=6 r18=3 s13=. s14=. s15=. s16=. s18=4 s19=8
10
Black 28 bending is not a good move, this move should be played as move 1 in Dia. 4. Although white may play A to make a seki, white also have defects, so black's situation is better than in Figure 1.
d4=. d16=. l18=8 l12=13 m14=10 m15=2 m16=4 m17=6 m18=7 n12=11 n14=. n15=1 n16=3 n17=5 n18=9 o13=. o14=. o15=. p11=. p12=. p13=. p14=. p15=. p16=. p17=. p18=A q4=. q12=. q13=. q14=. q15=. q16=. q18=. r8=12 r11=. r12=. r13=. r14=. r15=. r16=. s13=. s14=. s15=. s16=.
White 29 succeeds in building a wall and potential by giving up two stones. After white 39, although black gets 18 points at the lower-right corner, the central black group is very weak. It will be a very large burden for black in future combat. Up to now, white obtains some advantage from the lower-right corner fight.
Black 40 is not good, it should be played at 1 as shown in Dia. 5. It's a crucial point for the whole board. Next, regardless where white plays, for example, 2 or position A, black can play 3 to limit white's future development first, then play 5. If the game proceeds like this, the game is still a long way to go.
d4=. d16=. g17=A h16=2 k4=5 k15=3 k17=4 l12=1 n12=. n13=. n14=. n15=. n16=. n17=. n18=. o12=. o13=. o14=. o15=. o16=. o17=. o18=. p11=. p12=. p13=. p14=. p15=. p16=. p17=. p18=. q4=. q12=. q13=. q14=. q15=. q16=. q18=. r8=. r11=. r12=. r13=. r14=. r15=. r16=. s13=. s14=. s15=. s16=.
After white's quick-witted moves 41 and 43, the white wall is thicker and thicker, and the influence is stronger and stronger.
Black 48 is very reluctant, but black has to manage to play here. Otherwise, when white plays at 48, then the whole board is more unfavorable to black. White 49 is weak, this move should have been played at 50. Regardless wherever black plays, white will be in an advantageous position in fighting. After black 50 avoids the cut, the tension in the central part is relaxed a little bit, but overall, white is still leading.