Lesson
White to move. Main line: 1. Kf4 Re7 2. Qa6 Rd7 3. Qa5+ Ke8 4. Qb5 Ke7
The rook stays glued to its king, because a rook alone on an open board is picked off by checks and forks. So White cannot win it by attacking it — the king has to be forced away from it instead.
The method is zugzwang. White improves the king, then takes squares from the defenders with the queen, until Black runs out of moves that keep the rook protected. Every queen move here does one of those two jobs.
The tablebase rates this as a win in 47 moves with perfect play, which is the honest number: it is a technique to know, not a trick to spot. Over the board it is also why the fifty-move rule matters — the win exists, but only for a player who knows the method.
Why the extra material does not just win
Queen against rook looks like it should resolve itself. It does not, and the reason is that the rook never has to stand alone: it sits beside its king, defended, so there is nothing to attack and nothing to fork. A queen cannot win a piece that is protected by a king it cannot approach.
So the win is not about capturing the rook at all. It is about forcing the two defenders apart, and the only tool that does that is zugzwang — reaching a position where every legal move Black has breaks the connection.
The method, in the order it happens
First the attacking king walks in. A queen alone cannot create zugzwang, because the defender always has a spare rook move somewhere; the king is what removes those squares. This is why the line opens with a king move rather than a check.
Then the queen takes squares rather than giving checks. Checks feel productive and mostly are not: the defending king moves, the rook comes with it, and nothing has changed. Quiet queen moves that shrink the defenders’ box are what make progress.
Finally the rook is forced to a square where it can be taken with check or forked. That is the moment the ending is over, and everything before it exists to produce it.
The fifty-move rule is part of this ending
The tablebase rates this position as a win in 47 moves with perfect play from both sides. That is uncomfortably close to the fifty-move limit, and it is the practical fact that decides games: a player who knows the method wins, and a player who works it out at the board usually does not.
It also explains why strong defenders play this ending on rather than resigning. Objectively lost is not the same as lost in practice, and the defender only has to survive a fixed number of moves.
1.Kf4 (the line shown): Winning. The king comes closer before the queen commits to anything.
Early queen checks: Still winning on paper, but they make no progress: the king steps aside and the rook follows it.
Capturing the rook: Not available. It is defended, which is exactly what makes this a technique rather than a tactic.
Zugzwang, not attack, is what wins queen against rook — the defenders have to be forced apart.
Bring the king in first. A queen alone cannot take away the defender’s spare moves.
Checks that do not change anything are not progress; quiet moves that shrink the box are.
Know the move count. A 47-move win against a fifty-move limit is a race, and the defender knows it too.
Source: Syzygy endgame tablebases (via the Lichess tablebase API) — https://tablebase.lichess.ovh/standard
Source: The fifty-move rule — https://en.wikipedia.org/wiki/Fifty-move_rule