Nimzo-Indian Defense: Three Knights Variation, Korchnoi Variation
1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. Nf3 c5 5. d5
The Nimzo-Indian Defense: Three Knights Variation, Korchnoi Variation is a chess opening classified as ECO E21, reached after 1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. Nf3 c5 5. d5. It is a line of the Nimzo-Indian Defense. Black is to move. 1 named line continues from this position.
In 12.6 million rated Lichess games (blitz and slower), this position was reached 113 times by this move order. White won 43%, 7% were drawn and Black won 50%. The most popular continuation is 5… exd5 (40% of games).
Engine evaluation: −0.18 (Stockfish, depth 41; best line 5… O-O 6. g3 Bxc3+ 7. bxc3 exd5 8. cxd5)
- ECO
- E21
- Moves
- 9 plies
- FEN
rnbqk2r/pp1p1ppp/4pn2/2pP4/1bP5/2N2N2/PP2PPPP/R1BQKB1R b KQkq - 0 5- PGN
1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. Nf3 c5 5. d5
Analyse with Stockfish · Board image (SVG) · Open on Lichess
Results by rating
| Average rating | Games | White / draw / Black |
|---|---|---|
| 0-1499 | 11 | |
| 1500-1999 | 65 | |
| 2000+ | 37 | |
| All | 113 |
Most played moves
| Move | Games | White / draw / Black |
|---|---|---|
| 5… exd5 | 45 (40%) | |
| 5… d6 | 27 (24%) | |
| 5… O-O | 11 (10%) | |
| 5… Ne4 Three Knights Variation, Euwe Variation | 8 (7%) | |
| 5… Bxc3+ | 8 (7%) | |
| 5… b5 | 7 (6%) | |
| 5… Qa5 | 4 (4%) | |
| 5… a6 | 1 (1%) |
Master games
19 over-the-board games are classified under this line (White 47%, draw 6%, Black 47%). The strongest:
- GM Parham Maghsoodloo (2719) – GM Jan-Krzysztof Duda (2729) 1-0 · World Rapid 2022 · 2022-12-28
- GM Alexey Sarana (2674) – GM Andrey Drygalov (2457) 1-0 · Titled Tue 17th Dec Early · 2024-12-17
- FM Rudy Van Wessel (2387) – IM Alexander Kabatianski (2437) 1/2-1/2 · TCh-NED Meesterklasse 2013-14 · 2014-05-10
- IM Anatole Vlachos (2410) – FM Peter Keller (2377) 1-0 · Titled Tue 17th May Late · 2022-05-17
- Goran Urosevic (2239) – IM Ioannis Georgiadis (2445) 0-1 · 2nd Isthmia Open A · 2012-08-19
Highest-rated Lichess games
- IM LiVaEv (2527) – amirreza02 (2510) 1-0 · 2026-09-07 · 180 + 2s
- arkos_11 (2312) – KingsLeadHat (2496) 0-1 · 2026-09-04 · 180 + 2s
- Jeffypattu (2316) – Stallion28 (2479) 0-1 · 2026-09-06 · 600 + 0s
Comes from
Nimzo-Indian Defense: Three Knights Variation 1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. Nf3
Continuations
- Nimzo-Indian Defense: Three Knights Variation, Euwe Variation E21 · 1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. Nf3 c5 5. d5 Ne4
More Nimzo-Indian Defense lines (all)
- Nimzo-Indian Defense (3. Nc3 Bb4) E20
- Nimzo-Indian Defense: Dilworth Gambit E20
- Nimzo-Indian Defense: Kmoch Variation E20
- Nimzo-Indian Defense: Mikenas Attack E20
- Nimzo-Indian Defense: Romanishin Variation (3… Bb4 4. g3) E20
- Nimzo-Indian Defense: Romanishin Variation (5… O-O 6. Bg2) E20
- Nimzo-Indian Defense: Romanishin Variation, English Hybrid E20
- Nimzo-Indian Defense: Three Knights Variation, Shocron Gambit E21
- Nimzo-Indian Defense: Spielmann Variation E22
- Nimzo-Indian Defense: Spielmann Variation, Carlsbad Variation E23
- Nimzo-Indian Defense: Spielmann Variation, Romanovsky Gambit E23
- Nimzo-Indian Defense: Spielmann Variation, Stahlberg Variation (7. Bd2 Nxc5) E23
Opening names and moves from the Lichess openings dataset; statistics from the Lichess open database, 2026-09 (CC0), sample of 12.6 million games, bots excluded; evaluations from Lichess cloud analysis (all CC0). Master games from The Week in Chess #920–#1664 by Mark Crowther, used with permission.