Dovetail Mate

The Dovetail Mate (also called Cozio's Mate) is a checkmate in which a queen checks the king from a square diagonally next to it, while two of the king's escape squares are blocked by its own pieces. Those two blockers sit on the orthogonal squares away from the queen, and together with the king they make the notched shape of a dove's tail - which is where the name comes from. The queen is protected, so the king cannot capture it.

8

7

6

5

4

3

2

a1

b

c

d

e

f

g

h

Key pieceKey square

Why it is mate

The e5 king has eight neighbors, blocked in three different ways.

• d5, d4, e6, f6: the d6 queen covers all four - the d-file below it and the sixth rank beside it.
• f4: the king is checked along the d6-e5 diagonal, so stepping to f4 keeps it on that same diagonal - still in check, and illegal.
• e4, f5: not squares White attacks at all. Black's own pawns sit there, so the king cannot go.

The check cannot be answered either. Nothing can interpose on an adjacent check, and Kxd6 fails because the d1 rook defends the queen along the d-file.

The defender builds its own trap

The queen covers the file and the rank on its own. The two squares it does not reach - e4 and f5 - are shut by Black's own pawns.

8

7

6

5

4

3

2

a1

b

c

d

e

f

g

h

Key square

Take the two pawns off and Black gains Ke4 and Kf5. No white piece has moved, yet the mate is gone. Like its cousin the Swallowtail (below), the Dovetail depends on the king's own pieces filling the flight squares - the queen and its defender only supply the check.

Dovetail vs Swallowtail

The Dovetail is easy to confuse with the Swallowtail Mate, because both end with a protected queen right next to the king and two of the king's own pieces blocking its flight. The difference is the direction the queen checks from.

• Dovetail: the queen is diagonally next to the king. The two own-piece blockers sit on the orthogonal squares beside and behind it - the notch of the dove's tail.
• Swallowtail: the queen is orthogonally next to the king (straight in front). The two blockers sit on the diagonal squares behind it - the V of the tail.

Same ingredients, mirrored geometry. Fix which way the queen attacks and the rest of the picture follows.

A real finish

Below is an actual position from our puzzle set. The king on e7 is checked diagonally by the d6 queen, which the d1 rook defends; the king's own rook on e8 and pawn on f7 block the two orthogonal escape squares.

8

7

6

5

4

3

2

a1

b

c

d

e

f

g

h

Key piece

The blockers here are a rook and a pawn, and the king is still near its home square rather than in the middle of the board, but the mechanism is identical: a protected queen checking from the diagonal, the king's own pieces sealing the orthogonal flights.

On this site

Our puzzle database has 147 problems tagged as Dovetail Mate (counted September 2026), and 44% of them sit below rating 1200. It is the rarer of the two tails in our data (the Swallowtail has 331). One possible reason is that a diagonal check that also leaves exactly the right two orthogonal squares blocked is a more particular arrangement than the Swallowtail's straight check, but the counts alone do not show the cause. Not one puzzle in our data carries both this tag and the Swallowtail tag, so the two are tagged as separate patterns here.

Defending against it

• Keep an orthogonal escape. The trap needs both orthogonal flight squares sealed by your own pieces; if even one is open, the diagonal check is not mate.
• Mind a defended queen on a diagonal. A protected queen arriving on a square diagonally next to your king, with your own pieces boxing the straight flights, is the whole pattern - break it before it lands.
• Do not crowd your own king. As with the Swallowtail, the Dovetail almost always needs the king hemmed in by its own force; give it room in time.

References

• Lichess, puzzle theme Dovetail mate (the source of this site's puzzle tags). https://lichess.org/training/themes
• Wikipedia, Checkmate pattern - Dovetail (Cozio) and Swallowtail (Guéridon) definitions. https://en.wikipedia.org/wiki/Checkmate_pattern
• Statistics produced by scripts/analyze-theme-stats.ts; the run is recorded in docs/data/dovetailMate-stats.md.

---

Start training: Dovetail Mate training

Related: Swallowtail Mate · Back-Rank Mate · All tactics