Clearance sacrifice

A clearance sacrifice removes one of your own pieces from a square or line that another piece needs. The line may be a vertical file, a horizontal rank, or a diagonal. The obstructing piece makes a capture, gives check, meaning a direct attack on the king, or creates another threat. It is left to be taken, but its departure immediately frees the path for the follow-up.

The name is not used completely uniformly. Some sources call both the freeing of a line and the freeing of a square clearance. One classic classification separates line clearance from a sacrifice whose purpose is to vacate a square for another piece.

The apparent contradiction is the point: a valuable piece can also be an obstruction. If moving it opens a line toward the king, makes available a square from which another piece can attack the king with no legal answer, or lets a stronger piece enter, losing it may be the correct price. The follow-up usually creates a threat that demands an immediate reply, so the opponent has no time to close the line again or move the target away.

To test the idea, identify which friendly piece blocks the action and what exact resource appears after it moves. Then verify whether the clearing move creates an urgent threat, whether the piece must truly be sacrificed, and what defenses exist after both accepting and declining the offered piece.

The idea often forms part of a combination, a concrete sequence of connected moves. It differs from a deflection sacrifice because clearance removes a friendly obstruction, while deflection forces an enemy piece away from its duty.