King's Indian: 3.Nf3

King's Indian: 3.Nf3

Definition

“King’s Indian: 3.Nf3” designates the position reached after the moves
1. d4 Nf6 2. c4 g6 3. Nf3.
It is a branch of the King’s Indian Defence (KID) in which White develops the king’s knight before committing the c-knight to Nc3 or choosing a pawn set-up such as the Four-Pawns or Saëmisch. Because the move 3.Nf3 does not block the c-pawn and keeps the g-pawn free to advance, it is one of the most flexible ways to meet the KID, often transposing to the Fianchetto Variation, the Classical System, or even completely different openings like the Grünfeld Defence.

Typical Move Order and Transpositional Possibilities

After 1.d4 Nf6 2.c4 g6 3.Nf3, Black has several thematic replies:

• 3…Bg7 – Standard KID move.
  • 4.g3 O-O 5.Bg2 d6 → Fianchetto Variation (E60–E62).
  • 4.Nc3 d6 5.e4 → Classical KID (E94–E99).
  • 4.e3 O-O 5.Be2 d6 6.O-O → “Flexi-KID,” often compared to a Neo-Catalan.
• 3…d5 – Switches to the Grünfeld Defence (D90–D99).
• 3…c5 – Benoni style; if 4.d5, Black enters a Modern Benoni (A60–A79).
• 3…b6 – Hippopotamus or English Defence set-up.

Because both sides retain multiple set-up choices, books sometimes label 3.Nf3 as “unclassified KID” (E60) until the next few moves define the system.

Strategic Ideas for White

• Flexibility. By delaying Nc3 and the e-pawn advance, White waits to see whether Black chooses …d6 (KID) or …d5 (Grünfeld), then selects the most comfortable set-up.
• Limiting Black’s choices. Early Nf3 prevents …e5 lines where Black can quickly strike at d4 with …exd4 followed by …c5.
• Safe Fianchetto. The move order 3.Nf3 followed by g3 avoids annoying gambits such as the Panno line (…Nc6 …a6 …Rb8) because Nc3 may never be played.
• Potential for a Catalan-type squeeze. Plans with g3, Bg2, Qc2, Rd1 and d4–d5 place long-term positional pressure on Black’s queenside.

Strategic Ideas for Black

• Immediate Grünfeld. Playing …d5 on move 3 eliminates many of White’s pet Fianchetto systems and steers the game into Grünfeld theory.
• Classical KID set-up. If Black prefers the standard KID pawn structure, …d6 …O-O …e5 remains fully viable; the transposition occurs after White eventually plays Nc3 and e4.
• Benoni or Benko. With 3…c5 or 3…b5, Black can sidestep both KID and Grünfeld theory to reach sharp queenside-counterplay openings.

Historical Notes

• The 3.Nf3 move order gained popularity in the late 1980s when grandmasters such as Jonathan Speelman and John Nunn sought to avoid the ultra-theoretical Mar del Plata KID (with 3.Nc3).
• Vladimir Kramnik adopted it regularly in the 1990s, using the flexible Catalan-style set-up to score several key wins against Garry Kasparov, notably in Dortmund 1996.
• Modern elite practice (e.g., Carlsen, Giri, Ding) shows 3.Nf3 to be the most common reply to 2…g6, outnumbering 3.Nc3 in top database statistics.

Illustrative Mini-Game

The following abbreviated PGN shows an instructive strategic win for White featuring the typical Fianchetto set-up:

Interesting Facts & Anecdotes

• Secret preparation: Bobby Fischer experimented with 3.Nf3 in off-hand blitz sessions during the 1970 Candidates cycle, but never unveiled it in a tournament, keeping opponents guessing about his KID repertoire.
• On ChessBase’s 2022 Mega Database, 3.Nf3 scores a healthy 55 % for White across 85,000+ games—higher than both 3.Nc3 and 3.g3.
• Computer engines evaluate the initial 3.Nf3 position at roughly +0.25 pawns for White, reflecting a small but persistent space advantage.
• Because almost any Black reply leads to a different ECO code, some annotators humorously call 3.Nf3 the “E6-O passport”—you leave the terminal (E60) as soon as the next move is played.