Fourth File Rook

Fourth File Rook

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Fourth File Rook
with Mino Castle

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In shogi, Fourth File Rook (四間飛車 shikenbisha) is a class of Ranging Rook (振り飛車) openings (戦法) in which the rook (飛) is positioned on the fourth file if played by White (後手) or the sixth file if played by Black (先手).

History

Ohashi vs Hon'inbō 1607

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Ohashi vs Hon'inbō 1607

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The earliest recorded shogi game was a Static Rook vs. Fourth File Rook game from 1607. Black was Sokei Ohashi who played a Right Fourth File Rook position (Static Rook) against Hon'inbō Sansa's Fourth File Rook. Ohashi won the game.

Types of Fourth File Rook

Closing Bishop's Diagonal (Black)

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P-6f

Closing Bishop's Diagonal (White)

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P-4d

Traditionally, Fourth File Rook has been used as a defensive strategy for White used against Static Rook openings played by Black. This opening is named simply Fourth File Rook (四間飛車 shikenbisha). When the position is played by Black, then it is known as Black Fourth File Rook (先手四間飛車 sente shikenbisha).

Additionally, the standard way to play the position (both White and Black) is for the player to close their bishop (角) diagonal with a pawn (歩) advanced to the 6f square when played by Black or advanced to 4d when played by White. This is sometimes called Normal Fourth File Rook (ノーマル四間飛車 nōmaru shikenbisha) which contrasts with a Fourth File Rook position that allows a bishop exchange to occur at anytime, which is known as Bishop Exchange Fourth File Rook (角交換四間飛車 kaku kōkan shikenbisha) or Open Bishop Diagonal Fourth File Rook (角道オープン四間飛車 kaku michi ōpen shikenbisha).

Traditional Fourth File Rook

First moves

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Up to move 6

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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 first adjacent board position. (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. This left silver will likely be a main component of White's counterattack.

Against Black's Right Fourth File Rook

Against Right Fourth File Rook

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Against Right Fourth File Rook

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Against Right Fourth File Rook

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Against Right Fourth File Rook

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Against Right Fourth File Rook

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Against Right Fourth File Rook

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Against Right Fourth File Rook

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Against Right Fourth File Rook

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Against Right Fourth File Rook

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Against Right Fourth File Rook

△ pieces in hand: 銀歩

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▲ pieces in hand: 角銀歩

White's Fourth File Rook against Black's Right Fourth File Rook (右四間飛車 migi shikenbisha). ^[1]