The Dovetail Mate: The Queen Mates from One Diagonal Step Away
A dovetail mate is a checkmate in which a protected queen stands diagonally next to the king, and the two squares the queen does not cover are blocked by the king's own pieces.
The mating picture
Picture a black king on g7 and a white queen on h6, protected by a bishop on c1 far down the diagonal. The queen covers a lot: h7, h8, g6 and f6 directly, and f8 through the king along the diagonal. That leaves only two squares around the king that the queen cannot reach, g8 and f7. In the dovetail mate both of them are occupied by the king's own pieces, for example a rook on g8 and a pawn on f7.
The same picture can occur anywhere on the board, not just in the corner, as long as the queen is diagonally adjacent to the king and protected.
The typical lead-in
A queen check often drives the king onto the square where the dovetail closes. In practice the most common lead-in is a check along a file or diagonal that leaves the king a single legal move, followed by a quiet-looking queen move to the diagonal square next to it.
The queen must be protected, or the king simply captures it. The protection can come from far away: a bishop on its home square, a rook on the same file, or a pawn. Always check the long diagonals behind your queen before you rule out a mate.
Why it gets missed
The defender's own pieces do most of the work, so the position does not look like a mating attack. The rook on g8 and the pawn on f7 look like defenders, but they are taking away the king's squares. Whenever an enemy king has its own pieces right next to it, ask which squares those pieces are blocking. The queen mates you miss in your own games are good ones to drill.
How to spot it
- Look for an enemy king with its own pieces on the squares next to it.
- Find the square diagonally adjacent to the king where your queen could land.
- Check that something protects that square, even from far away.
- Count the king's remaining squares once the queen is there.
- Look for a queen check that forces the king onto the mating square first.
Try one
Work it out from the diagram first, then play it on the board or open the solution.
8
7
2
1a
c
hExample 1
White to move and mate in two.
Show solution
30.Qh5+ Kg7 31.Qh6#
Qh5+ checks the king on h7 along the h-file and covers g6, so with g8 occupied by its own rook the king must go to g7. Qh6# follows: the queen is protected by the bishop on c1 along the open c1-h6 diagonal, and it covers h7, h8, g6, f6 and f8. The only other squares, f7 and g8, are blocked by Black's own pawn and rook.
Position from a real game, via the Lichess puzzle database.