Openings · B20–B99

Sicilian Defence

The most played answer to 1.e4: an unbalanced game from move one, and a wing pawn traded for a centre pawn.

1.e4 c5played as Black

The idea

1…c5 refuses to mirror White. After the usual d4 and …cxd4, Black has traded a c-pawn for a d-pawn, owns the half-open c-file, and has a central pawn majority to play with later.

The price is that White gets a lead in development and an obvious attacking plan on the kingside. Sicilian games are races, and the person who understands their own plan better usually wins them regardless of the evaluation.

Practise the line

You play Black; the other side answers on its own. Nothing here is saved or graded.

Your move 1 of 10/1

1.e4c5

White is answering…

Common mistakes

Three that come up again and again below master level. Each is ordinary opening theory — a named trap, or the error every coach corrects — not a statistic, and not drawn from anybody's games.

Leaving b5 to the knight

1.e4 c5 2.Nf3 Nc6 3.d4 cxd4 4.Nxd4 e5

The mistake: Playing …e5 or …e6 with a pawn on d6 and no …a6, so a knight can land on b5.
Why it costs: The knight on b5 hits d6 and cannot be chased by a pawn. Whole variations exist to make …e5 work, and they all start by taking the b5 square away first.
Instead: …a6 is not a wasted move in the Sicilian — it is why so many Sicilians begin with it. Play it before the committal central move, not after.

Taking on b2

1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 Qb6

The mistake: Bringing the queen out to take the b2 pawn because it is there.
Why it costs: The queen wins a pawn and then spends three or four moves getting home while White develops with threats every time. In the Poisoned Pawn Najdorf this works, because sixty years of analysis say exactly how — outside those lines, it is a lead in development handed over for a pawn.
Instead: Finish developing. The Sicilian's counterplay comes down the c-file, not from raids on the queenside with the queen alone.

Castling one move too late

1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 g6 6.Be3 Bg7 7.f3 O-O 8.Qd2

The mistake: Playing one more useful-looking move before castling and getting the rook to c8.
Why it costs: Against the Dragon setup White's plan is fixed and fast — Be3, Qd2, f3, O-O-O, then h4 and h5. It is a race that is decided by a single tempo, and the attack does not have to be better than your counterplay, only quicker.
Instead: Castle, then …Rc8 and …Ne5, and get the knight to c4. Every move that is not part of the race is a move given away.

Where it fits

The lines out of it with pages of their own: Sicilian, Alapin, Sicilian, Closed, Sicilian, Smith–Morra Gambit, Sicilian, Accelerated Dragon, Sicilian, Classical, Sicilian, Dragon, Sicilian, Najdorf and Sicilian, Sveshnikov.

Try it on one of your own

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