QGA: 3.Nc3 a6 - Queen's Gambit Accepted
QGA: 3.Nc3 a6
Definition
“QGA: 3.Nc3 a6” designates a specific line of the Queen’s Gambit Accepted (QGA) that arises after the moves 1. d4 d5 2. c4 dxc4 3. Nc3 a6. After accepting White’s c-pawn, Black plays 3…a6 with the main intention of preparing …b5 to keep the pawn on c4 and seize queenside space. The position is catalogued in ECO code D20 and is sometimes referred to informally as the …a6 Variation or Polish / Stockholm Variation of the QGA.
Purpose of the Move …a6
- Pawn preservation: Preparing …b5 to cement the extra pawn on c4.
- Queenside expansion: …b5–b4 can drive away a knight on c3 and grab space.
- Flexibility: Black keeps central pawn breaks (…e5 or …c5) in reserve while asking White to decide how to regain the pawn.
- Psychological weapon: Avoids the heaviest theory of 3…Nf6 lines and forces White to play more “on his own.”
Typical Plans
For White
- Rapid central occupation: 4.e4 is principled, establishing a broad pawn centre while the c4-pawn is still outside the fight.
- Immediate undermining: 4.a4 directly challenges Black’s intended …b5.
- Development & pressure: Nf3, e3, Bxc4, and eventually Qe2–Rd1 to target the d-file.
For Black
- Queenside clamp: …b5, …Bb7, and sometimes …c5 to restrain White’s centre.
- Counter-centre: Timely …e5 (after …Nf6 and …e6) or …c5 to strike back.
- Piece activity: The light-squared bishop often lands on b7, the dark-squared bishop on e7 or d6, with rooks ready for …c5.
Strategic Imbalance
White enjoys a strong centre and lead in development, but Black possesses the extra pawn and a clear plan to undermine White’s centre later. If Black fails to consolidate, the c-pawn can become a long-term weakness; if Black succeeds, the queenside majority may decide the endgame.
Historical Background
Although less common than 3…Nf6 or 3…e5, the …a6 line has been tried by several creative grandmasters looking to sidestep mainstream theory—among them Svetozar Gligorić in the 1960s and Viktor Korchnoi in the 1970s. Modern engines give the move a respectable evaluation, so it occasionally re-emerges in contemporary practice as a surprise weapon.
Illustrative Continuations
-
4.e4 b5 5.Nf3 Nf6 6.a4 Bb7 7.e5 Nd5 8.axb5
Nxc3 9.bxc3
Both sides have staked claims: White owns the centre; Black keeps an outside passed a-pawn. -
4.a4 Nc6 5.Nf3 Nf6 6.e4 Bg4 7.Be3 e6 8.Bxc4
White regains the pawn quickly; Black relies on piece activity.
Famous Example
Gligorić – Korchnoi, Skopje 1968
1.d4 d5 2.c4 dxc4 3.Nc3 a6 4.Nf3 b5 5.e4 Bb7 6.Bf4 e6 7.Be2 Nf6
8.e5 Nd5 9.Nxd5 Qxd5 10.0-0 Be7 11.Qd2 …
Gligorić eventually converted his spatial advantage, illustrating
the practical dangers Black faces if his counterplay is delayed.
Interesting Facts & Anecdotes
- Because the move …a6 is so reminiscent of Slav structures, some authors jokingly dub the setup “Slav-Lite” inside a QGA framework.
- Engines rate 3…a6 around ±0.30 for White (depth 30+), i.e., fully playable but demanding accuracy.
- The line is a favorite sideline in correspondence chess, where Black players can prepare deep forcing sequences after …b5.
- In blitz, gambiteers sometimes try 4.e4 b5 5.a4, sacrificing a pawn for a huge lead in development—an echo of the Evans Gambit spirit.
Practical Tips
- White: Decide early between 4.e4 (central expansion) and 4.a4 (direct pawn recovery); mixing plans can concede the initiative.
- Black: Play …b5 quickly—delay invites 4.e4 followed by Bxc4, when the c-pawn drops without compensation.
- Both sides should watch the b1–h7 diagonal: after …e6, Black’s king can become drafty if the bishop on c1 eyes h7.
Further Study
Explore the databases for recent games by Ivan Šarić and David Navara, both of whom have tested 3…a6 in classical play. A deeper theoretical survey can be found in ECO D20 notes and in “Queen’s Gambit Accepted – A Repertoire for Black” by Raetsky & Chetverik.