Central Rook

In shogi, Central Rook (中飛車 nakabisha) is a special class of Ranging Rook (振り飛車) openings (戦法) in which the rook (飛) is positioned on the fifth (central) file. It is also possible to castle your king on the left after playing central rook.

The standard way to play Central Rook is for the player to close their bishop (角) diagonal with a pawn (歩) advanced to the 6f square when played by Black (先手) or advanced to 4d when played by White (後手). This is sometimes called ノーマル中飛車 nōmaru nakabisha "Normal Central Rook" which contrasts with a Central Rook position that allows a bishop exchange to occur at anytime, such as Cheerful Central Rook.

Games that have the bishop diagonal closed are known as slow games.

Ranging Rook strategies like Central are also traditionally played by White against Black's Static Rook (居飛車) position.

The Central Rook player will commonly use either a Mino (美濃囲い) or Anaguma (穴熊) castle. Since the rook is positioned on the fifth file, it prevents the player from making the usual Mino castle. Therefore, Central Rook's castle is often an Incomplete Mino (片美濃).

The opening starts by the usual four-move sequence that characterizes Static Rook vs Ranging Rook (居飛車対振り飛車) games as shown in the board position on the right. (See: Traditional Ranging Rook.)

3. S-4h. Black advances their right silver up and toward the center of the board. (This is a more flexible move than 3. S-3h.)

3. ... S-4b. White likewise moves their silver up and to toward the center. This move gives White the possibility of further moving the silver up to 6d through 5c (after a pawn push) as well to 4c or 3c. This left silver will likely be a main component of White's counterattack.

Although White also has the choice of moving their rook for this move (3. ... R-5b), moving their silver first instead keeps White's strategy more uncertain as well as giving White the option of playing a Double Yagura position (which is a Static Rook opening). This move, however, does delay ranging the rook to any other Ranging Rook positions on the fourth, third, and second files.

4. P-5f. This prepares for various Static Rook strategies.

4. ... P-5d.

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