The Frontal Defense in Rook Endgames

Watch the method: press play to see the winning idea run, or step through it move by move.

Philidor assumes your king reached the queening square. The short-side defense assumes it is at least nearby. The frontal defense is the method for the ugly case: your king is cut off on the wrong side entirely, and your rook must fight the pawn alone.

The setup. Park the rook directly in front of the pawn, as far away as possible. The pawn cannot advance through the rook, so progress requires the attacking king to step ahead of its pawn and escort it. That is your trigger: check from the front. With the whole file between you, the king cannot get at your rook, and it escapes the checks only by giving up the escort: back behind its own pawn, or sideways to the edge, where it guards nothing. As soon as it slips out of your checks that way, put your rook straight back in front of the pawn; one check too many there loses.

The two conditions. (1) The pawn must still be on its fourth rank or earlier: each advance shortens your checking runway, and past the midline the shelter squares in front do the attacker's work. (2) Keep at least three squares between your rook and the pawn; closer, and the king simply walks to your rook and asks it to leave.

Why it completes the set: with Philidor, the short-side defense and the frontal defense you have a drawing method for every placement of your king in rook and pawn versus rook. The attacker here never gives up a half point: it will probe the exact boundary of the technique, and one slow check lets the escort slip through.