2015年2月21日土曜日

Kiou Title Match

The 2nd game of Kiou Title Match between title holder Akira Watanabe and challenger Yoshiharu Habu has been played today. Kiou is held as a 5-game match, each game being played within one day. Habu has 4 titles of 7 and Watanabe has 2 of 7. This match is certainly top level shogi.
You can watch the game on thin site.
http://live.shogi.or.jp/kiou/kifu/40/kiou201502210101.html

▲S-46 strategy which is the most popular in Yagura  was selected. Against ▲S-46, pushing a pawn immediately with △P-45 and forcing the silver to pull back to 37 is recently increasing. Although this sequence seems like turn loss for sente, 45 will become the point sente attacks afterwards, such as ▲P-46 after ▲R-48 and ▲P-46 right away. △P-45 was not thought to be a good move due to the attack from ▲P-46, but, has been reconsidered nowadays. Watanabe with white adopted it in his recent several games.

Diag.1
In Diag.1, Habu played ▲Sx45 aggressively in reply to △P*45 again, despite the risk of bishop promotion and a lance loss. After gaining a silver, sente has a chop drop with ▲S*41 to make the castle weaker. He expected that.


Diag.2
About 10 moves later from Diag.1, the position was Diag.2. If sente's turn, ▲G*44 would be an aimed move. △Sx ▲Px △Gx ▲S*53 or △Gx ▲Px △Sx ▲B*51 △R-43 ▲G*42 would be an successful example for sente.Sente's castle is still safe compared to gote's. Here, △B*24 was a good counterattack. The place where the rook run to is difficult. When 47 or 49, there is a chop drop with △S*58. Also, when 48, △S*69 becomes an effective attack with a bishop's path and a silver. Generally, △S*69 is a typical technique to break a Yagura castle. I think Watanabe had an advantage at Diag.2.

Diag.3
Now, the position is Diag.3. Gote is much better, but, need to pay attention to the fork with ▲+B-64 or ▲Rx42+ △Kx ▲+B-64 next.
Here, Watanabe discarded a knight with △N*55 to remove the threat and after ▲Px, dropped △G*57. This move was a threatmate with △Gx68 ▲Sx △G*88 ▲Kx △+Rx68. Habu resigned at △G*57. Even if sente protects with ▲N*48, gote would almost win with △Gx67 ▲Gx △B*58 ▲G-68 △Bx49+. Next △+Rx48 will be a severe move, which serves as both attack and defense.

Watanabe took a 2-0 lead. He is a win away from defending his title.


2015年2月9日月曜日

Side Pawn Picker, △B*45 strategy (2)

Two moves are available in basic diagram. (1) △S*87 and (2) △N-33.

Basic Diagram

(1) △S*87 is a fierce attack with a silver sacrifice, which is threatening to make room forcibly for dropping a rook. If taken with gold, △R*79 would be dropped. After this, it would proceed with ▲K-48 △Bx67+ ▲S*58 △+Bx ▲Kx △R-78+ ▲P*68 △+Rx87 ▲P*88 △+R-78 ▲B*45 (Diag.1) or ▲L*69 △Bx67+ ▲S*58 △+Bx89 ▲P*64 △Px ▲+Bx21 (Diag.2). Actually, I think each case is slightly better for sente, but, according to past data, in reply to △S*87, ▲+B-77 (Diag.3) is selected in most games. If △Sx78+, after ▲+Bx, there would be no place to drop something in sente's camp.

Diag.1
Diag.2
Diag.3
In Diag.3, gote is supposed to play △Sx76=. If taken with +bishop, △R*26 would become a +bishop-silver fork. Many players avoid it and select ▲+B-68 safely. In fact, against △R*26, I suppose sente has a little advantage with ▲P*27 △Rx76 ▲S*77 although it might be a long game from △R-75.
After ▲+B-68, continuing with △P*88 ▲R*75 △Px89+ ▲Rx45, sente is slightly better also in this case. This line is more common than ▲+Bx76.


(2) △N-33 blockades the +bishop's path and aims at several strong moves next, such as △S*87, △S*66 and △R*26. Here, ▲L*36 (Diag.4) is said to be the strongest candidate for sente, although ▲R*86 and ▲R*21 are also considered.

Diag.4
Against △S*87 in Diag.4, it's not good to take it in this position because +bishop can't pull back on 77. If taken with gold, continuing with △R*79 ▲K-48 △Bx67+ ▲S*58 △+Bx ▲Kx △Rx89+ (Diag.5), gote would be better. Sente's king is in more trouble than gote's.

Diag.5
Therefore, ▲G-79 against △S*87 should be played instead of ▲Gx. After △Bx67+, it will go for mutual attack with ▲Lx33+ △S-78+ ▲Gx △+Bx ▲+Lx32 △Sx (Diag.6).

Diag.6
It seems like sente's king is more dangerous than gote's as the place of opponent's +bishop is close to his king. Actually, in Diag.6, early eacape with ▲K-48 make the king safety. Even if checked by △R*68, ▲G*58 would protect tightly. After ▲K-48, it will proceed with △+Bx89 ▲P*62 (Diag.7) △Kx ▲P*64.

Diag.7
▲P*62 is the pawn technique to capture the king quickly. In case of △Sx, the attack with ▲+B-22 would be severe because the left side is blocked by his own pieces. Also, in case of △Gx, ▲+B-22 as when △Sx would be a severe move, which is threatening to drop the rook on the 1st rank. In case of △Kx, ▲P*64 will be an effective attack to hit the vital point of the king's head. In each case, sente has an advantage at Diag.7.