Sicilian Defense: O'Kelly Variation

ECO B28beginner

The O'Kelly Variation is a trap with an opening attached: 1.e4 c5 2.Nf3 a6, a move that looks like a wasted tempo and is anything but. If White plays the automatic 3.d4, Black replies 3...cxd4 4.Nxd4 and then ...e5, hitting the knight with tempo in a version of the Sicilian that normally costs Black several moves to reach. The main line shown here, 3.c3 d5 4.exd5 Qxd5 5.d4 Nf6 6.Be2, is White's correct, unhurried answer.

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Main line

1.e4 c5 2.Nf3 a6 3.c3 d5 4.exd5 Qxd5 5.d4 Nf6 6.Be2

Diagram shows the position after 6 half-moves of the main line. On SpeakChess you can drill this line move by move — the trainer plays the other side and corrects you instantly, then spaced repetition schedules each variation so you review it right before you would forget it.

Move by move

The first 11 moves of the main line, explained one at a time. Every move of every variation is annotated like this inside the trainer — this page shows the opening moves so you can judge the explanations before signing up.

1.e4 What a great way to start! Your pawn marches up to e4, a light square right in the middle of the board. Taking the center early gives your other pieces lots of room to come out and play soon.
1...c5 Black plays c5, advancing the pawn two squares from its starting square. This is the Sicilian Defense, a standard response that indirectly challenges White's center.
2.Nf3 White moves their knight from g1 to f3. This is a good developing move that helps get your pieces into the game.
2...a6 Black moves the pawn from a7 to a6. This prepares a queenside expansion with ...b5, a common idea in this Sicilian Defense variation.
3.c3 You moved your pawn from c2 to c3. This prepares to advance your d-pawn to d4 next.
3...d5 Black pushes a pawn to d5, a light square in the middle. It is a brave move that plants a pawn in the center and gives Black's pieces extra space to spread out and join the game.
4.exd5 Your pawn on e4 captures the pawn on d5. This opens the e-file and influences the center.
4...Qxd5 Great move! Your queen comes out from her start square and takes a pawn right in the middle of the board. This helps your queen control lots of important squares in the middle of the game.
5.d4 Your d-pawn strides forward to d4, a dark square in the heart of the board. Now you have a strong pawn sitting proudly in the center, helping you grab space and feel at home in the middle.
5...Nf6 Black moves their knight from g8 to f6. This is a good developing move that helps get a piece into the game.
6.Be2 White moves their bishop from f1 to e2. This is a good developing move, getting a piece off the back row and into the game!

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Win rates by rating

Results from real online games, measured after the line shown in each row. Most opening sites show one aggregate number — how an opening scores depends heavily on who is playing it.

Rating	Games	White wins	Draws	Black wins	Position after
400-600	743	56.8%	5.9%	37.3%	1.e4 c5 2.Nf3
600-800	74	64.9%	1.4%	33.8%	1.e4 c5 2.Nf3 a6 3.c3
800-1000	28	57.1%	0%	42.9%	1.e4 c5 2.Nf3 a6 3.c3 d5 4.exd5 Qxd5 5.d4
1000-1200	288	47.9%	1.4%	50.7%	1.e4 c5 2.Nf3 a6 3.c3
1200-1400	39	64.1%	0%	35.9%	1.e4 c5 2.Nf3 a6 3.c3 d5 4.exd5 Qxd5 5.d4 Nf6
1400-1600	49	49%	4.1%	46.9%	1.e4 c5 2.Nf3 a6 3.c3 d5 4.exd5 Qxd5 5.d4 Nf6 6.Be2
1600-1800	49	40.8%	10.2%	49%	1.e4 c5 2.Nf3 a6 3.c3 d5 4.exd5 Qxd5 5.d4 Nf6
1800-2000	62	51.6%	4.8%	43.5%	1.e4 c5 2.Nf3 a6 3.c3 d5 4.exd5 Qxd5 5.d4 Nf6 6.Be2
2000-2200	82	52.4%	3.7%	43.9%	1.e4 c5 2.Nf3 a6 3.c3 d5 4.exd5 Qxd5 5.d4 Nf6 6.Be2
2200-2400	80	46.3%	12.5%	41.2%	1.e4 c5 2.Nf3 a6 3.c3 d5 4.exd5 Qxd5 5.d4 Nf6 6.Be2

Most played continuations (400-600 rating)

After 1.e4 c5 2.Nf3:

Nc6 — played 35.9% of the time (White wins 52.1%, draws 3.4%, Black wins 44.6%)
d6 — played 12.8% of the time (White wins 47.4%, draws 6.3%, Black wins 46.3%)
Nf6 — played 9.2% of the time (White wins 64.7%, draws 1.5%, Black wins 33.8%)

Related openings

Frequently asked questions

Why is 3.d4 a mistake against the O'Kelly?

Because after 3...cxd4 4.Nxd4 Black plays ...e5 immediately, kicking the knight and grabbing the centre. In a normal Open Sicilian that advance would leave d5 weak and cost time, but with ...a6 already played Black covers b5 and gains the tempo for free. White is not losing, but the ideal Open Sicilian setup is gone.

What should White play instead?

The main recommendations are 3.c3, heading for an Alapin structure as in the line here, or 3.c4, clamping down on d5 and b5 to make ...a6 genuinely useless. Both take the sting out of the move order. The practical lesson is that against 2...a6 you must think rather than play 3.d4 on autopilot.

Is the O'Kelly sound enough for serious play?

It is respectable but not a main line. Objectively 2...a6 is slightly slow, and against accurate play White keeps a small pull. As a practical surprise weapon at club and online blitz level it scores very well, because a large share of opponents will answer 3.d4 without a moment's thought.