Chess lessons › Checkmate patterns
The ladder mate
Two rooks push a lone king to the edge, one rank at a time.
The idea
The rooks take turns to check, pushing a lone king to the edge.
- One rook holds the seventh rank, so the king cannot step back.
- The other rook checks along the back rank.
- The king has run out of ranks: it is mate.
In a game: With both rooks against a lone king, check with one while the other holds the rank behind.
The lesson
Two rooks can mate a lone king with a simple method called the ladder. One rook checks along a rank. The other rook then jumps ahead and checks on the next rank, while the first one stops the king stepping back. Each check pushes the king one rung up the ladder, until it runs out of ranks.
Watch it from the middle of the board.
- 1. Rb5+ The first rook checks along the fifth rank. The king cannot stay there.
- 1... Kd6 2. Ra6+ The other rook checks one rank higher. The rook on b5 takes the fifth rank away, so the king cannot go back.
- 2... Kd7 3. Rb7+ Again the rook behind jumps ahead, this time to the seventh rank.
- 3... Kd8 4. Ra8# Checkmate on the eighth rank. The rook on b7 covers the whole seventh.
Find the move
White to move. The black king is on the back rank. Mate in two: first take the seventh rank away.
A hint
Put one rook on the seventh rank.
Show the answer
1. Rb7 Kf8 2. Ra8#
Either rook can go to the seventh rank, and then the king has only the eighth rank. Wherever it goes, the other rook gives mate there.
Find the move
The rook on b7 keeps the king off the seventh rank. Give mate with the other rook.
A hint
The king is on the eighth rank. Check it there.
Show the answer
1. Ra8#
Ra8 checks on the eighth rank. The rook on b7 covers the seventh, so the king has no square.
A question
While one rook gives check, what is the other rook doing?
Show the answer
Taking away the rank the king has just left, so it cannot step back.
Right. That is how the ladder works: the king can only go forwards, towards the edge.
Play it out
Now you play the ladder against the tablebase, which defends perfectly. Check with one rook, bring the other ahead of it, and keep both rooks away from the king so it cannot take them.
In the lesson you play this out on the board, against the endgame tablebase’s best defence.