Sicilian: O'Kelly, 3.d4 cxd4 4.Nxd4
Sicilian Defense: O’Kelly Variation – Main Line 1. e4 c5 2. Nf3 a6 3. d4 cxd4 4. Nxd4
Definition
The O’Kelly Variation is a branch of the Sicilian Defense that begins with
the slightly off-beat 2…a6. After White’s natural central thrust 3.d4, Black
captures once on d4 and White recaptures with the knight, reaching the
position that gives this definition its name:
The move 2…a6 is attributable to Belgian Grandmaster Albéric O’Kelly de
Galway (1911-1980), the 3rd World Correspondence Champion, who used it
regularly in the 1950s. Today it remains a dynamic sideline employed by
grandmasters seeking to avoid the most deeply analysed main-stream Open
Sicilians.
Strategic Ideas and Typical Plans
- Prophylaxis against 3.Bb5+ or 3.c3: By playing …a6 on move two, Black discourages the Rossolimo idea (3.Bb5+) and the Alapin set-up with an early c3, steering the game into fresh territory.
- Flexible development: Black can still choose between …e6, …d6, …Nc6, or even …g6 setups, waiting to see how White arranges his pieces before committing.
- Queenside space: The pawn on a6 supports a later …b5, grabbing space on the queenside and preparing …Bb7 or …Bb4.
- White’s central majority: After 4.Nxd4 White enjoys a lead in development and a central knight. Typical continuations include 4…Nf6 5.Nc3 e5 (striking the knight) or 4…e5 5.Nf3 Nc6, when White aims for rapid piece activity before Black completes development.
Typical Move Orders after 4.Nxd4
- 4…Nf6 5.Nc3 e5 6.Nf3 – the most popular line; Black kicks the d4-knight but concedes the d5-square.
- 4…e5 5.Nf3 Nc6 – Black delays …Nf6 and keeps the option of …Bc5 or …Bb4.
- 4…e6 – a Scheveningen-style set-up that may transpose to well-known lines after …d6 and …Nf6.
Historical Significance
Albéric O’Kelly de Galway unveiled the idea in top-level practice at the 1956 Candidates’ Tournament in Amsterdam, surprising several opponents. Though never as fashionable as the Najdorf or Scheveningen, the variation attracted a cult following among creative players such as Bent Larsen and, more recently, Teimour Radjabov and Alexei Shirov.
Illustrative Games
- O’Kelly de Galway – Pachman, Madrid 1960
The inventor’s fine win showing the power of an early …b5 and …Bb7 set-up. - Shirov – Radjabov, Linares 2003
A modern heavyweight clash where Black sacrificed the exchange for a long-term dark-square bind. - Carlsen – Nepomniachtchi, Wijk aan Zee 2011
World champions also dabble: Nepomniachtchi equalised comfortably with 4…e5 and later drew against Carlsen.
Common Tactical Motifs
- …d5 Breaks: Black often readies …d5 to challenge the centre once development is complete.
- e4-e5 Pawn Lever: White may push e5 at the right moment to seize space and fix the d6-square as a weakness.
- Outpost on d5: After …e5 and Nf3-d5, White’s knight can become an eternal nuisance if Black mis-times …d6.
Interesting Facts & Anecdotes
- O’Kelly allegedly devised 2…a6 during train rides, analysing on a pocket board while travelling to tournaments.
- The move was once nicknamed “the cowboy boot” because the black a-pawn sticks out to the side like a spur.
- In correspondence chess the line has a surprisingly high drawing percentage, reflecting its solid but flexible nature.
Practical Tips
- For Black: Be ready with multiple set-ups; the value of 2…a6 lies in transpositional freedom.
- For White: Exploit your lead in development. Quick Bc4, 0-0, and f4 ideas can put Black under pressure before …e6 and …d6 solidify the position.
Related Openings
The O’Kelly can transpose into or share ideas with the Najdorf Sicilian, the Scheveningen, and even some lines of the Taimanov where …a6 is inserted before …Nc6.