Sicilian Defence

1.e4 c5

You trade a wing pawn for White's centre pawn on move three and spend the rest of the game using the half-open c-file it leaves behind. Nothing is symmetrical, so nothing is a draw by default: you get real winning chances as Black, and the same six-move setup (...d6, ...Nf6, ...a6, ...e5, ...Be7, castle) works against everything White usually tries.

Spar this opening

Your setup

Knightf6
Knightd7 / c6
Bishope7 / g7
Bishope6 / d7 / b7
Queenc7
Rookc8
Pawnsc5 d6 a6
CastleO-O

a6 before e5. ...a6 first, then ...e5. The pawn on e5 leaves d5 and d6 soft, and White's knight would love to land on b5 to poke at them. ...a6 takes b5 away from the knight and from the bishop (no Bb5+). Play ...e5 before ...a6 and both arrive at once.

d6 before e5. ...d6 before ...e5. Without the d-pawn behind it, the e5-pawn is a target rather than a stake: 2.Nf3 e5 simply loses it to Nxe5. With ...d6 in place, ...e5 is a claim on the centre that White has to respect.

Ideas

The trade that defines the opening

The moment White plays d4, take it. Your c-pawn for their d-pawn is the whole deal.

A wing pawn for a centre pawn is a good exchange on its own. It also opens the c-file halfway for you and leaves White with no pawn on d4 to lean on. Nearly every Sicilian problem a beginner has comes from letting White play d4 and NOT taking, so that dxc5 or d5 arrives instead.

The Najdorf setup, every game

...d6, ...Nf6, ...a6, ...e5, ...Be7, castle. Then ...Be6, ...Nbd7, ...Qc7, ...Rc8.

The Open Sicilian is enormous, and you do not need any of it. Once the knights are out you play the same six moves in the same order. ...a6 stops the knight and bishop landing on b5; ...e5 kicks the d4-knight and claims the centre; ...Be7 and castling make the king safe. After that the pieces go to the same squares whatever White does.

The e4-pawn is never free

Once a knight sits on c3, ...Nxe4 just loses a knight for a pawn.

Your knight on f6 stares at e4 all game and the pawn always looks loose. It is defended by the c3-knight, and after ...Nxe4 Nxe4 you are a piece down for nothing. The only time to take on e4 is when NO knight is on c3 and no rook stands on e1. Your counterplay is ...b5, ...Rc8 and the ...d5 break, not a pawn grab.

Against c3: hit e4 with ...Nf6

2.c3 or the Morra 3.c3: play ...Nf6, hop to d5 after e5, and take on d4 the moment it appears.

White plays c3 to recapture on d4 with a pawn and keep a big centre. ...Nf6 forces a decision about e4 before that centre exists. After e5 Nd5 the knight is safe in the middle, your c-pawn still takes on d4, and White's e5-pawn becomes the target of ...d6. Against the Smith-Morra (2.d4 cxd4 3.c3) the same ...Nf6 declines the gambit and lands you in exactly this line, a pawn up in structure and with nothing to memorise.

Against Bb5+: block, trade, carry on

...Bd7, let them take, recapture with the queen, and develop as normal.

The check on b5 is White avoiding the Open Sicilian, not attacking you. Blocking with the bishop offers a trade that costs you nothing: your light bishop is the piece you have least use for behind a pawn on d6. After ...Qxd7 the queen is well placed on the d-file, and ...Nc6, ...Nf6, ...e6 and ...Be7 follow. If White ever leaves the b5-bishop unprotected, ...Bxb5 is simply a free piece.

Against f4 setups: bishop to g7

2.Nc3 and f4 is a kingside attack. Meet it with ...Nc6, ...g6, ...Bg7 and let the bishop watch the queenside.

The Grand Prix Attack wants f4, Bc4 or Bb5, and pieces pointing at your king. The fianchetto bishop on g7 is the ideal defender: it covers the dark squares White's f-pawn has loosened and hits d4 and b2 the moment the centre opens. Do not rush ...e5 or ...Nf6 here; e5 would be kicked by f5 and the knight by e5.

When the book runs out

Castle, then ...Be6, ...Nbd7, ...Qc7, ...Rc8. Fight for d5, and break with ...b5 or ...d5.

The Sicilian middlegame has a shape you can always fall back on. The queen and a rook go to the c-file. The light bishop guards d5, the one hole your ...e5 created. Then you pick a break: ...b5–b4 to kick the c3-knight and open the queenside, or ...d5 once enough pieces cover it. White will attack on the kingside; do not sit and defend, race them on the other wing.

The structure

The Najdorf picture: pawns on a6, d6 and e5, the half-open c-file for the queen and a rook, the bishop heading to e6 to guard d5, and ...b5 as the queenside break while White attacks on the other wing.

Traps

The e4-pawn is poisoned

e4 c5 Nf3 d6 d4 cxd4 Nxd4 Nf6 Nc3 Nxe4 Nxe4

The tell: Your knight on f6 stares at e4 and nothing seems to guard it.

The c3-knight does. After ...Nxe4 Nxe4 you have given a knight for a pawn on move five. This is the single most common Sicilian blunder under 1200, and it repeats: the same pawn looks free after Be2, after Nb3, after castling. It never is while a knight sits on c3.

The greedy Alapin pawn

e4 c5 c3 Nf6 e5 Nd5 d4 cxd4 Nf3 dxc3 Qxd5

The tell: You have a pawn on d4, White has just played Nf3, and c3 is there for the taking.

Taking on c3 opens the d-file, and your knight on d5 has no defender yet. Qxd5 takes it for free. Play ...e6 first: it guards the knight, and then ...dxc3 or ...d6 are both fine.

The knight that forgot about a6

e4 c5 Nf3 d6 d4 cxd4 Nxd4 Nf6 Nc3 a6 Be2 e5 Ndb5 axb5

The tell: You play ...e5, the knight on d4 is attacked, and White remembers that knights like b5 in the Sicilian.

That is exactly what ...a6 was for. The knight hops to b5 and the a-pawn takes it. The other ways White can lose the piece here are just as common: Bg5, Be3 or castling while the knight is attacked all lose it to ...exd4.

Model games

Najdorf main line: the setup, then the ...d5 break

e4 c5 Nf3 d6 d4 cxd4 Nxd4 Nf6 Nc3 a6 Be2 e5 Nb3 Be7 O-O O-O Be3 Be6 f4 exf4 Bxf4 Nc6 Kh1 d5 exd5 Nxd5

The whole setup in order: ...d6, ...Nf6, ...a6, ...e5, ...Be7, castle, ...Be6. When White breaks with f4 you take, develop the last knight, and the ...d5 break frees your game completely.

Alapin: dismantle the centre

e4 c5 c3 Nf6 e5 Nd5 d4 cxd4 Nf3 e6 cxd4 d6 Bc4 Nc6 O-O Be7 exd6 Qxd6 Nc3 Nxc3 bxc3 O-O

...Nf6 makes White push e5, ...cxd4 and ...d6 hit the centre, and after exd6 Qxd6 the queen looks at an isolated d4-pawn. Castle, ...Rd8, ...b6 and ...Bb7 all point the same way.

Moscow: trade the bishop and block the centre

e4 c5 Nf3 d6 Bb5+ Bd7 Bxd7+ Qxd7 O-O Nc6 c3 Nf6 Re1 e6 d4 cxd4 cxd4 d5 e5 Ne4 Nbd2 Nxd2 Bxd2 Be7

Block the check, recapture with the queen, develop normally. When d4 comes you take, block with ...d5, and the knight on e4 is a rock until it trades itself for White's best piece.

How the coach grades a move

Every move you play gets one of six grades, from the engine’s view of the position, with the book’s verdict taking over when it is harsher. The sentence beside it is always the reason. Tap it for what the move did, why this opening wants it, and whether anything was better.

Best: Nothing better was available.
Good: Within a few percent of best. Noise at this depth.
Playable: A small real gap. The better move is named, play goes on.
Inaccuracy: Seven to twelve points of winning chances. The game stops to show you.
Mistake: Twelve or more, or a move the book warns against, or a broken order rule.
Blunder: Twenty-five or more. Usually material.

Catalogued as B20–B99 in the Encyclopaedia of Chess Openings, the reference index most databases sort by.