Tarrasch rule
The Tarrasch rule holds that a rook usually belongs behind a passed pawn, whether the pawn is its own or the enemy's, because from the rear the rook gains squares as the pawn moves up instead of losing them.
Also called: rooks belong behind passed pawns
Count the squares a rook can use on the pawn's file and the rule explains itself. A rook behind a pawn gains a square each time the pawn moves up, while a rook in front loses one every time, until it is boxed against the edge with nothing to do.
With your own passed pawn, a rook at the rear backs up every step without blocking anything, so the pawn can march while the rook stays put. Against an enemy passed pawn, a rook at the rear keeps the pawn under fire all the way up the board, so the opponent must keep guarding it, while your rook's file only gets longer as the pawn advances.
The guideline carries the name of Siegbert Tarrasch, who stated it for rook endings, and it holds far more often than not. It still has exceptions. A rook in front of an enemy pawn can be the right blockade when your king is far away and the pawn would otherwise run, and a rook placed to the side can be better when it also cuts the enemy king off from the pawn.
Before each pawn move in a rook ending, check which side of the pawn each rook stands on. The side whose rook is behind usually has the easier game.
It sits close to Passive rook. A passive rook is stuck guarding a pawn or a square, often on its back rank or in front of its own pawn, with little scope to attack, so the opponent's pieces gain time and room.
Endgame ideas like "Tarrasch rule" are won or lost on small details, which a coach can check in your own games. The first lesson with George Li is where that review starts.
Related terms
A passed pawn has a clear road to promotion as far as enemy pawns are concerned: none stands ahead of it on its own file or the two neighboring files, so the opponent must spend a piece or the king to stop it.
An active rook controls open lines, attacks enemy pawns or the king from behind or the side, and cannot easily be attacked, which makes it far stronger than a rook that merely sits and defends.
A passive rook is stuck guarding a pawn or a square, often on its back rank or in front of its own pawn, with little scope to attack, so the opponent's pieces gain time and room.
A rook endgame is an ending in which each side has a rook and some pawns and no other pieces, and it is the most common type of endgame, so its main ideas are worth learning early.
Cutting off the king means placing a rook on a file or rank so that the enemy king cannot cross it, which keeps the king away from the pawns and often makes a rook ending easy to win.
Guides that go further
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