Pterodactyl Defense: Sicilian, Unpin (B27)

The Sicilian, Unpin is a variation of the Pterodactyl Defense, catalogued as ECO B27. The line runs 1. e4 c5 2. Nf3 g6 3. d4 Bg7 4. Nc3 Qa5 5. Bd2, reaching the position shown below after 9 half-moves.

White holds the centre with pawns on d4 and e4, and one pawn capture is available, so the structure has not settled yet. White is ahead in development, with three minor pieces out to Black's one. It is Black to move after five moves.

On the Pterodactyl Defense generally: ECO A40. A chess opening with 34 known variations.

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Pterodactyl Defense: Sicilian, Unpin — position after Bd2 a8b7c6d5e4f3g2h1
Position after 1. e4 c5 2. Nf3 g6 3. d4 Bg7 4. Nc3 Qa5 5. Bd2

Move order

#WhiteBlack
1e4c5
2Nf3g6
3d4Bg7
4Nc3Qa5
5Bd2

ECO: B27

Stockfish: 0.00 at depth 18

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Position characteristics

Related Pterodactyl Defense lines

Frequently asked questions

What are the moves of the Sicilian, Unpin?

The Sicilian, Unpin goes 1. e4 c5 2. Nf3 g6 3. d4 Bg7 4. Nc3 Qa5 5. Bd2. It is a variation of the Pterodactyl Defense and is catalogued as ECO B27.

What is the ECO code for the Sicilian, Unpin?

The Sicilian, Unpin is ECO B27. ECO codes group openings by their move order, so nearby codes cover closely related lines of the Pterodactyl Defense.

Is the Sicilian, Unpin good for White?

Stockfish evaluates the position after 1. e4 c5 2. Nf3 g6 3. d4 Bg7 4. Nc3 Qa5 5. Bd2 at 0.00 at depth 18, which is balanced. Engine evaluation is only a starting point — at club level the practical value of a line is mostly about whether you know its plans better than your opponent does.

What kind of position does the Sicilian, Unpin lead to?

White holds the centre with pawns on d4 and e4, and one pawn capture is available, so the structure has not settled yet. White is ahead in development, with three minor pieces out to Black's one. It is Black to move.