French: Tarrasch, Closed, Nunn-Korchnoi Gambit

French: Tarrasch

Definition

The French Defence, Tarrasch Variation arises after the moves 1. e4 e6 2. d4 d5 3. Nd2. By placing the knight on d2 instead of c3, White keeps the c-pawn free and sidesteps some of Black’s sharpest replies (most notably the Winawer with 3…Bb4). The ECO codes are C03–C09.

Typical Move Orders

Two of the most common branches are:

• 3…Nf6 4. e5 Nfd7 5. Bd3 / c3 – the “Closed” Tarrasch, often leading to the Guimard, Rubinstein or Nunn-Korchnoi lines.
• 3…c5 4. exd5 exd5 – the Open System, where Black immediately strikes in the centre.

Strategic Ideas

• Flexibility. The c-pawn can advance to c3 or c4 depending on circumstances, while the b-knight can later find routes via f3 or b3.
• Solid centre. White keeps a pawn on d4 and usually maintains the e-pawn, aiming for the classical pawn chain e5–d4 versus Black’s e6–d5.
• Piece activity vs. structure. Black often obtains active piece play (…c5, …Nc6, …Qb6) at the cost of a somewhat cramped light-squared bishop.

Historical Significance

Named after Dr. Siegbert Tarrasch (1862-1934), who championed the idea that 3.Nd2 offers White a sound strategic foundation. The variation enjoyed a renaissance in the 1970s thanks to Anatoly Karpov, whose world-title matches against Viktor Korchnoi featured a wealth of high-level novelties.

Illustrative Example

In the following miniature, White exploits an over-optimistic Black setup:

Interesting Facts

• Because 3.Nd2 appears quiet, many club players are surprised by its latent attacking potential; several famous king-side crushes start from seemingly dry Tarrasch positions.
• The line is popular among correspondence and engine players because of its strategic richness and relatively low forcing content.

Closed

Definition

“Closed” is a descriptive term for both openings and positions in which pawn chains lock the centre, greatly limiting the immediate mobility of pieces and files. Typical closed structures feature few open lines, demanding long-term manoeuvring rather than direct tactical assaults.

How It Is Used

• Opening classification. The family of 1.d4 d5 systems is called the Closed Games (as opposed to 1.e4 e5 “Open Games”). Examples: Queen’s Gambit Declined, Colle System.
• Positional description. Regardless of opening, analysts say “the position is closed” when the pawn centre is locked—for instance after the Advance French setup e5 vs. …d5/e6.

Strategic Themes

1. Pawn breaks. Because lines are blocked, timely pawn ruptures (…f6, …c5 or f4, g4, etc.) become the chief means of opening the game.
2. Piece reroutes. Knights often excel, travelling circuitous routes to ideal outposts (e.g., Nf3–d2–f1–e3–g4 in many King’s Indian structures).
3. Space advantage. The side with more space can shift pieces behind its pawn chain faster, gaining the upper hand once the position opens.

Historical & Practical Significance

Closed play gained respect through the games of Wilhelm Steinitz and Emanuel Lasker, who demonstrated that restrained, strategic manoeuvres could neutralise the romantic 19th-century attacking style. Modern engines corroborate the richness of closed play—positions may stay “quiet” for 20 moves before exploding.

Example Position

After 1. d4 Nf6 2. c4 g6 3. Nc3 Bg7 4. e4 d6 5. f3 O-O 6. Be3, the King’s Indian Sämisch pawn chain d6–e5 vs. d4–e4 is firmly closed. Both sides will spend many moves preparing the thematic breaks …c6–b5–c5 (Black) or d5/f4 (White).

Interesting Anecdote

In the 1971 Candidates match, Bobby Fischer famously won a “closed” position against Mark Taimanov, gradually out-manoeuvring his opponent for 50 moves before a single file opened.

Nunn-Korchnoi Gambit

Definition

The Nunn-Korchnoi Gambit is an aggressive pawn sacrifice for Black in the French Defence, Tarrasch Variation (Closed System). Black plays …f6 at an early stage, offering a pawn to blast open the centre and activate the pieces.

Canonical Move Order

The most illustrative sequence is:

1. e4 e6
2. d4 d5
3. Nd2 Nf6
4. e5 Nfd7
5. Bd3 c5
6. c3 Nc6
7. Ne2 f6!?  (the gambit)

After 8. exf6 Nxf6 9. O-O, Black has yielded a central pawn but enjoys:

• Rapid development (…Bd6, …O-O).
• Pressure on d4 and the semi-open f-file.
• Potential attacking chances if White castles short.

Strategic & Practical Considerations

• Initiative vs. Material. Black banks on fast piece play; if the momentum falters, the extra pawn tells.
• King placement. White often delays castling, sometimes opting for long-side safety to blunt the f-file attack.
• Pawn structure. Even if Black regains the pawn, an isolani on e5/d4 may remain as a long-term target.

Origins & Name

Viktor Korchnoi employed the idea in the late 1960s, but it was Grandmaster John Nunn who conducted pioneering computer-assisted analysis in the 1980s, refining the concept into a cohesive gambit system—hence the double-barrelled name.

Illustrative Game

Korchnoi-Vaganian, Leningrad 1973, is a classic demonstration:

Although Black never recovered the pawn, the bishops and central pressure gave ample compensation and the game was eventually drawn after a tense fight.

Interesting Facts

• Engines initially frowned on the gambit, but modern neural-network evaluations often give Black full equality or more, sparking a small revival in correspondence play.
• Korchnoi used the idea against Karpov in the 1978 World Championship, achieving a comfortable draw despite being pawn down.
• Some theoreticians refer to 7…f6 as the “Poisoned Pawn” of the Tarrasch—tempting for White to accept, but filled with hidden dangers.