Sicilian Najdorf
Initial Moves: 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6
Strategic Summary & Main Idea
The Najdorf (1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6) is the most studied line in the Sicilian and the one least explained by the move it is named after: ...a6 develops nothing and attacks nothing. What it does is deny b5 to White's knight and bishop and prepare ...b5, buying Black the right to postpone every other decision. The position measures +0.32, and White's sixth move decides the kind of game — from +0.09 with 6.Bc4 to +0.48 with the Bg5 Attack.
The pawn structure this opening produces
The Najdorf inherits the open Sicilian structure and adds a choice: after ...e5 or ...e6, Black's centre holds two pawns against one, and d5 becomes the position's permanent hole. With ...e5 the hole is immediate and the c8-bishop comes out freely to e6; with ...e6 the pawn guards d5 and the bishop stays boxed in longer. Either way White's game is the same in spirit: occupy d5 with a piece Black cannot trade off, and open a line at the king before the ...b5-b4 counter reaches the c3-knight. Once White castles queenside the game becomes a declared pawn race, and move order starts to matter more than material.
Typical Plans for White
- English Attack: Be3, f3, Qd2, castle long and push g4-g5 at the f6-knight
- The 6.Bg5 Attack: immediate pressure on f6 and e7, with f4 and long castling — the more theoretical of the two
- Opocensky with 6.Be2: short castling, the a4 plan, and trading Black's light-squared bishop for a knight on d5
- Dodge the theory with 6.h3 or 6.g3, accepting half a tenth of a pawn less for almost no memorisation
Typical Plans for Black
- Choose the structure on move six: ...e5 frees the c8-bishop, ...e6 guards d5 for longer
- Expand with ...b5, ...Bb7 and ...Nbd7, hitting the c3-knight, which is what guards d5
- Break with ...d5 once development allows it — the move that settles the opening at a stroke
- Against queenside castling, race first: ...a5-a4 and ...b4 arrive before g5 in a good many lines
Main Variations of the Sicilian Najdorf
| Variation | Move Sequence | Evaluation | Style / Characteristic |
|---|---|---|---|
| English Attack | 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.Be3 e5 7.Nb3 Be6 8.f3 Be7 9.Qd2 |
+0.39 | The main line: opposite castling, a pawn race and concrete theory on both sides |
| Bg5 Attack | 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.Bg5 e6 7.f4 Be7 8.Qf3 Qc7 9.O-O-O |
+0.48 | The sharpest and the one that pays most, at the cost of the heaviest theory load |
| Opocensky (6.Be2) | 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.Be2 e5 7.Nb3 Be7 8.O-O O-O 9.Be3 |
+0.27 | Short castling and positional play; half the theory for half the edge |
| 6.f3 | 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.f3 |
+0.35 | Prepares the English Attack without handing Black's queen the b6 square |
| 6.h3 | 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.h3 |
+0.26 | Saves g4 for White's pawn rather than Black's knight; little theory |
| 6.Bc4 (Fischer-Sozin) | 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.Bc4 |
+0.09 | Points the bishop at f7 and, measured, is the sixth move that pays White least |
| 6.g3 | 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.g3 |
+0.12 | Fianchetto aimed at the d5 hole, with slow play and no forced lines |
Evaluations measured by us with Stockfish 19, depth 22, on 14 Sep 2026.
Frequently asked questions
What is White's best sixth move against the Najdorf?
By the evaluations measured here, the Bg5 Attack (+0.48) and the English Attack (+0.39). But both carry the heaviest theory load in the 1.e4 repertoire, and the gap to 6.h3 (+0.26) is about two tenths of a pawn — in practice, less than what is lost playing from memory a line you do not understand.
Is the Najdorf Poisoned Pawn still playable?
It is, and the engine does not refute it: after 6.Bg5 e6 7.f4 Qb6 8.Qd2 Qxb2 9.Rb1 Qa3 the position measures 0.00. Black is a pawn up with the queen far from home, and White's compensation is exactly enough. This is concrete theory on both sides, not a trap.
Why is ...a6 the most played move in the Sicilian?
Because it denies two squares — b5 to the knight and to the bishop — and commits to nothing. Black can still choose ...e5 or ...e6 next move, and it is that flexibility, rather than the pawn itself, that explains the popularity.
Guides on this opening
- How to build an opening repertoire: 1.c4 as White and the Sicilian as Black
- The Sicilian Defense for intermediate players: strategic plans and the tactics that decide games
- The Smith-Morra Gambit: a practical guide to facing the Sicilian a pawn down
- The Four Knights Sicilian: the main line, the check that fails and the test the engine prefers
- The Sicilian Kan: a guide to 4...a6, its plans and what the move costs
- Attacking sacrifice themes against the Sicilian: what makes them sound
- Sicilian Najdorf: a White repertoire with the English Attack and the quieter 6.Be2
- Sicilian Dragon: a Yugoslav Attack repertoire with opposite-side castling
Common Mistakes & Where Most Amateurs Go Wrong
- 01 White following the memorised English Attack sequence without looking at the board: after 6...e5 the d4-knight is attacked by a pawn, and f3 drops it on the spot. The line:
1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.Be3 e5 7.f3−3.71 - 02 Black playing ...b5 before ...e5: the d5 square and the a4-e8 diagonal are left unguarded, and a4 opens the file against the pawn that moved. The line:
1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.Be3 b5 7.a4+0.77
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