King's Indian: 4.Nf3 d6 5.Bf4 6.e3
King’s Indian: 4.Nf3 d6 5.Bf4 O-O 6.e3 (Bf4–e3 System)
Definition
This variation appears in the King’s Indian Defence after
1.d4 Nf6 2.c4 g6 3.Nc3 Bg7 4.Nf3 d6 5.Bf4 O-O 6.e3.
White develops the queen’s bishop before locking it in with e3,
chooses a restrained centre (pawns on c4–d4–e3), and often aims for
positional pressure rather than the hand-to-hand tactical skirmishes
typical of the main lines with 4.e4.
Typical Move Order
The most common sequence is:
- 1. d4 Nf6
- 2. c4 g6
- 3. Nc3 Bg7
- 4. Nf3 d6
- 5. Bf4 O-O (Black can also insert 5…c5 first.)
- 6. e3
The early Bf4 discourages …e5, while the modest pawn chain resembles a London System with an extra pinch of King’s-Indian spice.
Strategic Ideas for White
- Grip on e5: Nf3 and Bf4 jointly restrain …e5. If Black pushes it anyway, dxe5 often yields a lasting target on e5.
- Queenside expansion: Plans with Rc1, Qb3, a2–a3, and b2-b4 seek space and play on the flank where Black is less active.
- Flexible pawn breaks: White may choose c4-c5, d4-d5, or even e3-e4, depending on Black’s set-up.
- Harmonious piece placement: Dark-squared bishop usually lands on e2 or d3; the queen heads to c2 or b3; rooks occupy c1 and d1.
Strategic Ideas for Black
- …c5 break: With …e5 less attractive, Black often hits the d-pawn base instead.
- Kingside play: Manoeuvres such as …Nbd7, …Re8, …Nh5 and a later …f5 can still generate familiar KID attacking chances.
- Pressure on c4: Pieces converge on the c-file—…Rc8, …Qa5, …Be6—hoping to exploit an isolated or backward pawn after d4-d5.
Historical & Practical Significance
- Anatoly Karpov adopted this calmer system in the late 1970s, fitting his squeeze-oriented style.
- Boris Gelfand and Peter Svidler revived it in the 1990s-2000s as a reliable anti-KID weapon.
- Magnus Carlsen has employed the line several times, including a notable victory over Hikaru Nakamura at Wijk aan Zee 2015.
Model Game
Carlsen – Nakamura, Tata Steel 2015
Carlsen neutralised Black’s counterplay, fixed the e5-square, and steered the game into a favourable end-game he duly converted.
Typical Tactical Motifs
- e3-e4 break: If Black delays …e5 and …c5, White can seize space and unleash the Bf4.
- Exchange sacrifice on c5: dxc5 followed by Rxc5! can shatter Black’s queenside pawn structure.
- Minority attack: a2-a3 and b2-b4-b5 undermine the c-pawn, echoing Queen’s-Gambit themes.
Interesting Facts & Anecdotes
- The line once had a dubious reputation because Bf4 seemed to block the f-pawn, but engine evaluations now show it is fully sound.
- Vishy Anand used the system as surprise preparation against Boris Gelfand during the 2013 Candidates, valuing its solidity.
- The set-up is essentially a “King’s Indian London,” exploiting the fact that Black has already committed to …g6, weakening dark squares.
Why Choose This Line?
If you prefer strategic manoeuvring, long-term pressure, and reduced forcing lines, this system is an excellent practical choice—especially against King’s-Indian specialists who prepare sharp 4.e4 main lines.