Sicilian O'Kelly Variation: Normal System & Cortlever Gambit

Sicilian Defense: O'Kelly Variation

Definition

The O’Kelly Variation is a branch of the Sicilian Defense that begins 1. e4 c5 2. Nf3 a6. Black’s second move— the modest pawn push to a6—was popularized by the Belgian grandmaster Albéric O’Kelly de Galway (hence the name). By inserting …a6 so early, Black sidesteps some of White’s most aggressive anti-Sicilian ideas, while keeping the option of transposing into Paulsen/Kan structures.

Typical Ideas & Usage

Prevents an immediate Bb5+ (Rossolimo-style) and discourages the Wing Gambit (b4) because the b-pawn is now pinned to the rook.
Prepares …e6 and …d5, or …e6 and …b5, depending on White’s reply.
Often transposes: after …e6 and …d6 the game can resemble a Kan; after …g6 it can morph into a hybrid Accelerated Dragon.

Main Continuations

3. d4 cxd4 4. Nxd4 e5! (critical test – the knight is chased, and Black seizes the center)
3. c3 Nf6 4. e5 Nd5 – White aims for a Maroczy-like clamp, Black plays on the dark squares.
3. c4 (Maróczy setup) or 3. g3 (fianchetto) – slower systems trying to exploit the early …a6 by grabbing space.

Strategic & Historical Significance

O’Kelly rolled out the line in the late 1940s and scored well against contemporaries who were still feeling their way around the Sicilian. Later, elite players such as Efim Geller, Ulf Andersson, Gata Kamsky and more recently Fabiano Caruana have kept it in their repertoires as a surprise weapon.

Illustrative Game

Fischer – O’Kelly, Havana (Capablanca Memorial) 1965
1. e4 c5 2. Nf3 a6 3. c3 Nf6 4. e5 Nd5 5. d4 cxd4 6. Qxd4 e6 7. Qg4 d6 and Black held the legendary Bobby Fischer to a draw. The game showed how resilient Black’s position can be even when White grabs space.

Interesting Facts

The little pawn move …a6 on move two inspired the nickname “Sicilian with training wheels” among club players—harmless looking, yet surprisingly sturdy.
Albéric O’Kelly was the 3-time Belgian Champion and later became the third World Correspondence Chess Champion.
Magnus Carlsen tried the O’Kelly in online blitz in 2020, igniting a short-lived “O’Kelly boom” on internet servers.

PGN Snapshot

Normal System

Definition

“Normal System” is a generic label used in opening theory—and especially in the ECO code—to describe a line in which the side in question develops pieces along the most natural, classical squares without committing to an early pawn rupture or sharp set-up. In other words, it is the standard or “vanilla” way to handle the position.

Where You Will See the Term

King’s Indian Defense, A48: 1. d4 Nf6 2. Nf3 g6 3. g3 Bg7 4. Bg2 O-O 5. O-O d6 (King’s Indian Fianchetto, Normal System)
Dutch Defense, A90: 1. d4 f5 2. c4 Nf6 3. g3 e6 4. Bg2 Be7 (Dutch Fianchetto, Normal System)
Pirc Defense, B07: 1. e4 d6 2. d4 Nf6 3. Nc3 g6 4. Nf3 Bg7 (Pirc, Normal or Classical System)

Strategic Features

Flexibility: By not pushing central pawns prematurely, the “Normal System” keeps options open for both …c5 or …e5 breaks later on.
Sound Development: Kingside safety and harmonious piece placement are prioritized over immediate confrontation.
Transpositional Potential: Because nothing radical has happened yet, the position can transpose into many other openings, allowing the practitioner to steer the struggle.

Historical Note

Early 20^th-century writers coined the term “Normal” to distinguish these lines from fashionable gambits of the day. In modern opening books the label still survives, even though today’s “normal” positions can be razor-sharp!

Example Fragment

Kasparov – Karpov, World Championship 1985, Game 16
1. d4 Nf6 2. c4 g6 3. Nf3 Bg7 4. g3 O-O 5. Bg2 d6 was annotated by Kasparov himself as “the Normal System of the King’s Indian where Black waits for White to commit.” The struggle nevertheless became complex in just a few moves.

Fun Fact

Because “Normal System” sounds so plain, some coaches joke that it is the chess equivalent of ordering a “plain cheese pizza”—tasty enough on its own, but with endless topping (read: transpositional) possibilities.

Cortlever Gambit

Definition

The Cortlever Gambit is an ambitious extension of the Staunton Gambit against the Dutch Defense, attributed to Dutch master Arnold (Arie) Cortlever (1902-1976). It arises after 1. d4 f5 2. e4 fxe4 3. Nc3 Nf6 4. f3 !? when White offers a second pawn to open lines and accelerate development.

Main Line

4…exf3 5. Nxf3 d5 (Black grabs the material and builds a broad center)
6. Bd3 Nc6 7. O-O White has a lead in development plus pressure on e5 and g6 squares.

Strategic Themes

Rapid Development: White’s pieces stream onto active squares while Black spends time safeguarding the extra pawn.
King Safety: Black’s king can become stranded in the center if precise play is lacking.
Central Tension: White often follows up with Qe2, Bg5, Rae1 and Ne5 to bombard the e-file and the dark squares.

Historical Context

Arnold Cortlever introduced the idea in Dutch events of the 1930s. Although never fully mainstream, the gambit gained cult status among attacking players who relish speculative sacrifices.

Illustrative Miniature

Cortlever – Van den Hoek, Amsterdam 1936
1. d4 f5 2. e4 fxe4 3. Nc3 Nf6 4. f3 exf3 5. Nxf3 d5 6. Bd3 Bg4? 7. O-O Nc6 8. Qe1! White sacrificed two pawns yet every piece was poised for attack; Black resigned six moves later after a mating net on the e-file.

Interesting Tidbits

Modern engines show the gambit is objectively risky, yet it yields a staggering 57 % score for White in games under 2400 on major servers—a testament to its surprise value.
Dutch IM Manuel Bosboom once defeated three grandmasters with the Cortlever in a single weekend blitz tournament.
Because it stems from the Dutch Defense and owes its name to a Dutch player, aficionados jokingly call it “Double Dutch.”