52nd Oi Match Game 4

[Black "Hirose Akihito, Oi"]
[White "Habu Yoshiharu, Challenger"]
[Event "52nd Oi-sen, Game 4"]
[Date "August 9th and 10th 2011"]
1.P7g-7f     00:01:00  00:00:00
2.P3c-3d     00:01:00  00:01:00
3.P2g-2f     00:03:00  00:01:00
4.P8c-8d     00:03:00  00:03:00
5.P2f-2e     00:05:00  00:03:00
6.P8d-8e     00:05:00  00:04:00
7.G6i-7h     00:06:00  00:04:00
8.G4a-3b     00:06:00  00:05:00
9.P2e-2d     00:09:00  00:05:00
10.P2cx2d    00:09:00  00:07:00
11.R2hx2d    00:09:00  00:07:00
12.P8e-8f    00:09:00  00:09:00
13.P8gx8f    00:09:00  00:09:00
14.R8bx8f    00:09:00  00:10:00
15.R2dx3d    00:11:00  00:10:00
16.B2b-3c    00:11:00  00:12:00
17.K5i-5h    00:18:00  00:12:00
18.S3a-2b    00:18:00  00:29:00
19.R3d-3f    00:22:00  00:29:00
20.K5a-4a    00:22:00  00:32:00
21.P*8g      00:40:00  00:32:00
22.R8f-8e    00:40:00  00:35:00

Like in game 2, Hirose pushes the pawn in front of the rook on the third move, 
indicating that he wants to play Ibisha. Habu selects the R8e-Yokofudori with the 
creator of this opening Chuza watching in the press room. Chuza said that he thought 
the R8e-Yokofudori was a possibility, because Habu had played it on July 30th against 
Miura in the A Junisen as well (a game he won), but he was still surprised when his 
creation actually appeared on the board.

23.R3f-2f    00:41:00  00:35:00
24.S7a-6b    00:41:00  00:38:00
25.G4i-3h    00:45:00  00:38:00
26.G6a-5a    00:45:00  00:43:00
27.P3g-3f    01:05:00  00:43:00

Diagram 1

28.P*2e      01:05:00  01:04:00

It may have been that Hirose counted on Habu playing 28.P7d here. Then it follows 
29.N3g N7c S4h P*2e R2i and black will switch the rook to the left on the bottom 
file. This is what Habu played in the third game of last year's Ryu-O match against 
Watanabe (a game he won). There have been twelve games played like this and the result 
is split: 6-6. However, recently the black side has won 4 in a row, so maybe Hirose 
hoped to lure Habu into this type of position. Instead, Habu changes his earlier play
with 28.P*2e instead. This is not a new move and we are not in unknown territory yet. 
Not by long shot...

29.R2f-2h    01:09:00  01:04:00
30.P7c-7d    01:09:00  01:05:00
31.S3i-4h    01:27:00  01:05:00
32.P*8f      01:27:00  01:17:00
33.P8gx8f    01:30:00  01:17:00
34.R8ex8f    01:30:00  01:17:00
35.P4g-4f    01:39:00  01:17:00
36.R8fx7f    01:39:00  01:39:00
37.B8hx3c+   01:46:00  01:39:00
38.N2ax3c    01:46:00  01:39:00
39.S4h-4g    01:50:00  01:39:00
40.P2e-2f    01:50:00  01:50:00
41.P*8h      02:29:00  01:50:00
42.R7f-7e    02:29:00  02:27:00
43.R2hx2f    02:46:00  02:27:00
44.B*4d      02:46:00  02:39:00
45.P3f-3e    02:47:00  02:39:00
46.B4dx8h+   02:47:00  02:47:00
47.P*7f      02:48:00  02:47:00
48.R7ex7f    02:48:00  02:58:00
49.P*7g      02:50:00  02:58:00
50.+B8hx7h   02:50:00  02:59:00
51.S7ix7h    02:51:00  02:59:00
52.R7f-8f    02:51:00  02:59:00
53.P*8g      02:59:00  02:59:00
54.R8f-8e    02:59:00  03:00:00

Diagram 2

Looks pretty wild, but this position still has been played before. Despite the loss 
of material, the white pieces are working well, so the general opinion was that 
white can put up a good fight here.

55.S4g-3f    03:31:00  03:00:00
56.P*8h      03:31:00  03:16:00
57.P3e-3d    03:48:00  03:16:00
58.P*2c      03:48:00  03:20:00
59.N2i-3g    04:10:00  03:20:00

The sealed move.

60.P8hx8i+   04:10:00  03:46:00
61.S7hx8i    04:11:00  03:46:00
62.R8ex8g+   04:11:00  03:47:00
63.R2f-2i    04:13:00  03:47:00
64.P*8h      04:13:00  04:06:00
65.B*9h      04:20:00  04:06:00
66.+R8g-8f   04:20:00  04:20:00
67.P3dx3c+   04:46:00  04:20:00
68.S2bx3c    04:46:00  04:23:00
69.N3g-4e    04:48:00  04:23:00
70.N*5d      04:48:00  04:59:00
71.B9hx5d    05:03:00  04:59:00
72.P5cx5d    05:03:00  05:01:00
73.N4ex3c+   05:03:00  05:01:00
74.G3bx3c    05:03:00  05:03:00
75.N*4e      05:05:00  05:03:00
76.G3c-3b    05:05:00  05:05:00
77.P*3c      05:07:00  05:05:00
78.G3b-4b    05:07:00  05:05:00
79.R2ix2c+   05:12:00  05:05:00
80.P*3a      05:12:00  05:34:00

Diagram 3

81.+R2c-2b   06:08:00  05:34:00

Hirose took 56 minutes for this move and in the end decides that he cannot stray 
from the known path here. Despite the consensus that white has good chances, the 
position is complex and needs thorough calculation. For example, 81.N*3d is a move 
black wants to play and after 82.Px8i+ Nx4b+ Gx4b G*3b K5b Gx4b K6a G5b Kx5b S*5c 
Sx5c Nx5c+ Kx5c S*4d white has to be careful because Px4d P3b+ white must drop 
something on 4c and then black can pick up the rook with B*4b followed by Bx8f+. 
The correct answer to S*4d is K5b and the black attack is not decisive. For example,
 +R2b N*4b G*5c K6a G6b Kx6b B*5c K7c Bx8f+ and even though black has again captured 
the white rook, too much material was given up and white can win with S*6i Kx6i B*4i 
and there is no defense.

82.P8hx8i+   06:08:00  06:01:00
83.+R2bx3a   06:18:00  06:01:00
84.K4a-5b    06:18:00  06:01:00
85.P3c-3b+   06:28:00  06:01:00
86.+R8f-8h   06:28:00  06:02:00
87.N*6h      06:38:00  06:02:00
88.G*4a      06:38:00  06:22:00
89.+P3bx4b   06:47:00  06:22:00
90.G5ax4b    06:47:00  06:22:00
91.+R3ax1a   06:47:00  06:22:00
92.B*6i      06:47:00  06:49:00
93.K5hx6i    06:48:00  06:49:00
94.S*4i      06:48:00  06:49:00
95.L*5c      06:50:00  06:49:00

Diagram 4

96.S6bx5c    06:50:00  06:50:00

Finally, a new move. The game between Hatakeyama Mamoru and Inoue. Played last August 
in the B1 Junisen continued with 96.K6a and even though white won that game, the 
conclusion of the post-mortem analysis was that 96.Sx5c was even better. Habu new 
this (and Hirose said he knew this as well), but still thought the position was 
quite complicated.

97.N4ex5c+   07:06:00  06:50:00
98.K5bx5c    07:06:00  06:50:00
99.B*2f      07:08:00  06:50:00
100.L*4d     07:08:00  06:53:00
101.K6i-5i   07:08:00  06:53:00
102.S4ix3h+  07:08:00  06:54:00
103.S3f-3e   07:11:00  06:54:00
104.G*4h     07:11:00  07:21:00
105.B2fx4h   07:11:00  07:21:00
106.+S3hx4h  07:11:00  07:21:00
107.K5ix4h   07:11:00  07:21:00
108.+R8hx6h  07:11:00  07:21:00
109.K4h-3g   07:26:00  07:21:00
110.B*5i     07:26:00  07:21:00
111.K3g-2g   07:26:00  07:21:00
112.N*2c     07:26:00  07:21:00
113.S*2d     07:51:00  07:21:00
114.N2cx3e   07:51:00  07:36:00
115.S2dx3e   07:51:00  07:36:00
116.+R6hx5g  07:51:00  07:38:00
117.K2g-3f   07:51:00  07:38:00

Diagram 5

118.B5i-3g+  07:51:00  07:39:00

Hard to question this move, because it is safely winning, but in the press room the 
computer announced mate in this position. However, the top professionals Morishita, 
Fukauara, Akutsu and Sato Shinichi (who were all present for this game played in 
the southern city of Kita-Kyushu) couldn't find the mate. The problem is the position 
after 118.+R3g K2e +R2g P*2f Bx2f+ Sx2f S*3f K3e P*3d Kx3d P*3c. Now K2c +Rx2f P*2d 
G4b-3b K1b S*2c is easy, but no-one could figure out how to mate the king after K3e. 
In the end, the help of the computer was again needed to show the mate that even 
surprised both Hirose and Habu. The point is that after K3e N*2c K2d +Rx2f Kx1c, 
black plays S*2d!. This move is very hard to find for a human player, because it 
chases the king up the board, which is something that normally should be avoided. 
After S*2d K1b +R1e K2a G3a Kx3a +Rx1a and if black drops something on 2a, the R*4a 
is mate. It is unlikely that Habu put much thought in finding a mate in this position,
because he took only one minute to play 118.B3g+.

119.K3f-2e   07:51:00  07:39:00
120.S*2c     07:51:00  07:39:00
121.P*3c     07:58:00  07:39:00
122.P*2d     07:58:00  07:44:00
123.S3ex2d   07:58:00  07:44:00
124.+B3g-4g  07:58:00  07:45:00
125.N*3f     07:58:00  07:45:00
126.+R5gx4f  07:58:00  07:46:00
127.G*3e     07:58:00  07:46:00
128.S2c-1d   07:58:00  07:47:00
Resigns      07:58:00  07:47:00

Final Diagram

Mate after 129.K3d +B5f or 129.K2f +R3g K1f +B3h. There is no mate after 129.K1f, 
but then 130.+Bx3f is hisshi, so Hirose resigned here. It is a little bit of a 
mystery what Hirose was thinking when he followed a line that was considered bad 
for black for such a long time. He said after the game that he knew the theory, 
but that he thought black had a chance. However, there wasn't any point in the 
game where he played something to back up this opinion. Habu wins two in a row 
and the fifth game now becomes very important, as this match is now down to a 
best-of-three.