Openings · 横歩取り
Side Pawn Capture.
Take the loose pawn on the side of the board with the rook, and find out whether the two moves it cost matter.
The idea
The name of this opening is a move: the rook capturing the pawn that stands on the side of the board with nothing defending it. It only exists because of what came just before: both rook pawns are exchanged, White has spent two moves capturing on the eighth file, and that is exactly the time Black uses to take the pawn.
So Black is a pawn up and behind in development, White is a pawn down with a rook on an open file, and neither king has moved. That last part is the point rather than an oversight: castling costs moves that neither side has to spare. It is the sharpest opening in shogi, and whole systems in it are named after single moves.
How it goes together
Both sides’ moves are shown, because this opening is an agreement rather than a system: one player cannot reach it alone, so a one-sided list of moves would be a fiction.
Step through the moves, or press play.
Tap a move to jump to it. Arrow keys work once the board has focus.
Every move of the line, with reasons
| # | Black | White | Why |
|---|---|---|---|
| 1 | ▲７六歩 7g7f | △３四歩 3c3d | The pawn that will be taken, thirteen moves from now. |
| 3 | ▲２六歩 2g2f | △８四歩 8c8d | |
| 5 | ▲２五歩 2f2e | △８五歩 8d8e | |
| 7 | ▲７八金 6i7h | △３二金 4a3b | The gold guards the bishop’s head. Both sides want this before the files open. |
| 9 | ▲２四歩 2e2d | △同歩 2c2d | The first break. |
| 11 | ▲同飛 2h2d | △８六歩 8e8f | The rook takes back, and the pawns are level again. Now White does the same thing on the other wing. |
| 13 | ▲同歩 8g8f | △同飛 8b8f | And takes back with the rook. Both rooks are loose on open files. |
| 15 | ▲３四飛 2d3d | △３三角 2b3c | The side pawn. This is the move the opening is named after, and it is only possible because White spent two moves on the eighth file. The bishop comes up to 3c, which stops Black trading bishops on 2b. |
| 17 | ▲３六飛 3d3f | △２二銀 3a2b | Back to safety, and the rook on 3f is the one everybody studies. |
| 19 | ▲８七歩 P*8g | △８五飛 8f8e | A pawn from hand, to push the rook off 8f. And White’s rook settles on 8e: Chūza’s Rook (中座飛車). Neither king has castled, and neither will for a while. |
The plan once you are set up
- Know one line properly or play something else. This is the one opening here where a half-remembered move order loses on the spot.
- Guard the bishop’s head before anything opens. In a position with no castle, 7g and 3c decide most of the games.
- Spend the extra pawn on tempo rather than on greed. The pawn you captured is worth a move; a second one usually costs two.
- When the position settles, get the king somewhere. A middlegame king on 5i with both rooks active is how these games are lost.
What to watch for
- Bishop drops, on both sides. Once the pawns come off, both bishops have open diagonals and both players usually have a pawn in hand.
- The rook on 3f. It looks safe, and it is the target of half the theory in this opening.
- Your own move order. Swapping two moves here is not an inaccuracy, it is often a lost rook.
What it is played against
Another static rook, and only by agreement: White can decline at several points and often should. Watch a few games before playing one, because this is the professionals’ battleground rather than a beginner’s opening.
The line above ends on White’s rook pulled back only as far as 8e: that is Chūza’s Rook, a line with a page of its own. The older retreat to 8d is the Side Pawn Bishop-33, whose page links Black’s answers to it.
Play it against the bot.
The bot’s search levels, 9 to 12, open from a book that holds two of these openings, the Fourth File Rook and the Yagura; the Mino levels play the openings people play. Either way the review afterwards shows you where the game left the line. Try the line, then try the plan.