QGA: 3.Nf3 Bg4

QGA: 3.Nf3 Bg4

Definition

The sequence 1.d4 d5 2.c4 dxc4 3.Nf3 Bg4 is a branch of the Queen’s Gambit Accepted (QGA). After accepting the pawn on c4, Black immediately pins White’s knight on f3 with 3…Bg4, instead of the more popular 3…Nf6 or 3…e6. The variation is sometimes called the “Alekhine Variation” or simply the “Early …Bg4 System” in the QGA.

Move Order & Basic Ideas

The critical starting position arises after:

1. 1.d4 d5
2. 2.c4 dxc4 (Queen’s Gambit Accepted)
3. 3.Nf3 Bg4

Black’s 3…Bg4 aims to:

• Pin the knight on f3 to indirectly pressure the d4-square.
• Provoke weaknesses if White tries to break the pin too early (e.g., h3 or e3).
• Save time: the bishop moves once to g4 and can retreat later, whereas in other QGA lines Black must spend a tempo on …e6 before developing the bishop.

White, meanwhile, usually chooses between:

• 4.e3 – The solid main line, preparing to recapture the c4-pawn with Bxc4 and blunting the g4-bishop.
• 4.Ne5 – An aggressive sideline chasing the c4-pawn at once and asking Black to justify the early pin.
• 4.Nc3 or 4.Qa4+ – Less common tries aimed at tactical pressure.

Strategic Themes

Because Black has committed the bishop outside the pawn chain before playing …e6, typical QGA pawn structures shift:

• The bishop on g4 can be a strong piece if it maintains the pin, but it can become a target after h3, g4, or Qb3.
• Black must decide when to play …e6 (locking the bishop) versus …c5 (counter-attacking the center).
• The extra tempo gained from not playing …Nf6 immediately might help Black hold the c4-pawn for longer, forcing White’s bishop to lose a tempo recapturing.

Historical & Theoretical Background

The line appeared in the 1920s, with early investigations by Alexander Alekhine, hence its occasional name. It never became a mainstream QGA main line, but it has been used as a surprise weapon by strong grandmasters.

Modern engines show the position as dynamically equal, but practical experience indicates that unfamiliar opponents often react inaccurately, making it attractive for Black in rapid or blitz.

Model Game

A classic illustration of Black’s ideas:

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In this 1984 friendly training game between Ulf Andersson and Jan Timman, Black held the balance and later seized the initiative on the queenside.

Typical Tactics & Tricks

• Pin Motif: After 4.e3, if White immediately plays 5.Bxc4, 5…e6 6.Nc3 Nc6 can intensify pressure on d4 because Nxd4 is sometimes possible thanks to the pin.
• Counter-punch …e5: In positions where White castles kingside early, Black can consider …e5, breaking in the center while the bishop still eyes f3.
• h3?! Bxf3!? Occasionally Black gives up the bishop pair to damage White’s structure, then plays …e6 and …c5 with equal chances.

Illustrative Evaluation Table

• After 4.e3 e6 5.Bxc4 Nf6 6.h3 Bh5 7.Nc3, engines rate the position ≈ 0.10–0.20 — balanced but flexible for both sides.
• After 4.Ne5! Be6 5.e3, White scores slightly better in practice (≈ 55 % over thousands of games in databases).

Interesting Facts & Anecdotes

• Alekhine tried the move 3…Bg4 in simultaneous exhibitions to take opponents out of book early; he reportedly called it “a practical roulette — mostly safe, occasionally brilliant.”
• The line is a cousin of the Slav’s Winawer Counter-Gambit (…Bg4 ideas) and can transpose to certain Slav-like structures if Black later plays …c6.
• Grandmaster Sergei Tiviakov, known for deep opening preparation, once used 3…Bg4 to draw comfortably against Viswanathan Anand in a 2002 Bundesliga game.

When to Use It

• If you enjoy dynamic piece play rather than lengthy endgame squeezes.
• When facing a well-prepared Queen’s Gambit player and you wish to sidestep heavy theory.
• Particularly effective in faster time controls, where unfamiliar positions can yield valuable minutes on the opponent’s clock.