The Lucena Position
The Lucena position shows up constantly in rook endgames: you're up a pawn that's one step from promoting, but the defending rook is checking your king from behind, and every attempt to shield it seems to run out of squares. The winning method — known as "building a bridge" — uses your own rook to block the checks so your king can walk the pawn home.
White to move. The pawn is one square from promoting, but the black rook's checks look like they hold the position — until the bridge is built.
Key ideas
- Get your rook to the fourth rank on the file next to the pawn — this is the "bridge."
- When the defending rook checks, your rook interposes on the fourth rank, blocking the check.
- Your king then walks up in front of the pawn and shields it, and the pawn promotes on the next move.
- The technique works with any pawn except a rook pawn (a- or h-file) — those endings are usually drawn instead.
Common mistakes
- Trying to push the king forward before building the bridge — the checks just keep coming.
- Putting the rook on the wrong rank — the bridge only works from the fourth rank relative to the pawn.
- Not recognising the position at all and instead trying to trade down, throwing away a win.