Nimzo-Indian: Classical, Noa, Exchange, 6.Bg5
Nimzo-Indian: Classical (4.Qc2)
Definition
The Classical or Rubinstein Variation of the Nimzo-Indian Defence arises after the moves
1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. Qc2.
White immediately unpins the knight on c3 with the queen while keeping the option of recapturing on c3 with the queen rather than the b-pawn if ...Bxc3+ follows.
Strategic Ideas
- Avoiding Doubled Pawns: The queen on c2 protects the knight, so Black cannot inflict the traditional doubled c-pawns without giving up bishop for knight and allowing Qxc3.
- Central Control: White often follows with e4, gaining a broad pawn centre.
- Black’s Counterplay: Black usually plays ...d5 or ...c5 to undermine the centre, and may delay castling to retain the tension with ...Nc6 or ...d6.
Main Branches
- 4…d5 5. a3 Bxc3+ 6. Qxc3 – the Exchange Classical (see below).
- 4…O-O 5. a3 Bxc3+ 6. Qxc3 d5 – the most common modern setup.
- 4…c5 – immediate Queenside counterplay, echoing the Tarrasch Defence.
Historical Notes
Akiba Rubinstein used 4.Qc2 as early as 1913 against Alekhine, but the line gained mainstream popularity only in the 1980s when Garry Kasparov and the Soviet school revived it as a principal Anti-Nimzo weapon.
Illustrative Game
Anand – Kasparov, PCA World Championship 1995 (Game 10)
Kasparov unleashed 4…Nc6!?, a dynamic sideline, and eventually won a model game for Black’s counter-attacking chances.
Interesting Fact
An enduring joke among grandmasters is that the Classical is only “classical” because one must memorize a library of theory the size of the classics to play it well!
Nimzo-Indian: Noa Variation (4.e3 d5)
Definition
The Noa (or “Noah”) Variation begins
1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. e3 d5.
Unlike 4.Qc2, White plays the modest 4.e3, and Black immediately strikes in the centre with ...d5, accepting an isolated-queen-pawn structure after potential …dxc4 or ...c5 breaks.
Strategic Themes
- Solid Structure: White’s pawns on d4 and e3 form a compact shield, but the light-squared bishop is temporarily hemmed in.
- Isolated Queen’s Pawn (IQP): After 5.cxd5 exd5 6.Nf3, play often transposes to IQP positions reminiscent of the Queen’s Gambit Tarrasch.
- Minor-Piece Play: Because pawn tension is fixed early, both sides manoeuvre knights and bishops for outposts on e4, c4, and e5.
Typical Continuations
- 5. a3 Bxc3+ 6. bxc3 – White accepts doubled pawns but gains the bishop pair.
- 5. Nf3 O-O 6. Bd3 c5 7. O-O dxc4 – a modern favourite, treating the position like a Queen’s Gambit.
Origin of the Name
The variation is named after Dutch master Johann Jacob Noa (1843-1920), who explored these structures in late-19th-century correspondence games.
Famous Example
Karpov – Kortchnoi, Candidates Final 1978 (Game 7)
Karpov squeezed a small endgame advantage from the Noa structure to secure an eventual victory, demonstrating the power of a minimal-risk strategy.
Anecdote
Analyst Peter Svidler once quipped that the Noa line “doesn’t part the seas, but it does keep Black’s position afloat.”
Nimzo-Indian: Exchange
Definition
Any Nimzo line in which White forces the early exchange …Bxc3+ and recaptures with a queen or pawn is broadly called an Exchange Variation. The two most common routes are:
- 4.Qc2 O-O 5.a3 Bxc3+ 6.Qxc3 – Rubinstein-Classical Exchange.
- 4.a3 Bxc3+ 5.bxc3 – Saemisch Exchange (often followed by …O-O 6.Bg5, covered below).
Key Concepts
- Bishop Pair vs. Structure: White accepts doubled c-pawns to gain the two bishops; Black relies on pawn-structure targets and dark-square control.
- Open Files: The half-open b- and c-files give White natural rook activity. Black counters on the e- and f-files or via …c5.
- Piece Placement: Black’s remaining dark-squared bishop often lands on b7 or a6; knights aim for d7/f6/e4.
Historical Significance
The Exchange idea was a favourite of Botvinnik, who believed in “the two bishops in an open position.” His game vs. Capablanca (AVRO 1938) remains a strategic classic.
Model Game
Botvinnik – Capablanca, AVRO 1938
Botvinnik unleashed a long-term squeeze on the light squares, proving that a damaged structure can be outweighed by the bishop pair. The game is frequently cited in endgame literature.
Trivia
World Champion Magnus Carlsen has used the Exchange line as Black and White, once remarking, “If both players hate their own pawn structure, the one who copes better wins.”
Nimzo-Indian: 6.Bg5 (Saemisch, 6.Bg5)
Definition
This continuation is reached from the Saemisch Exchange line:
1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. a3 Bxc3+ 5. bxc3 O-O 6. Bg5.
By pinning the knight on f6, White seeks rapid development and kingside pressure to compensate for the weakened c-pawn structure.
Strategic Motifs
- Direct Pin: Bg5 discourages ...d5 because of cxd5 exd5 Bxf6 Qxf6 Nxd5, exploiting tactics on c7 and f6.
- Flexible Centre: White can choose between e3–f3–e4 pawn storms or a restrained setup with e3, Nf3, Bd3.
- Black’s Counterplay: Black often counters with …c5, …h6, …b6, and a later …Ba6 to exchange dark-squared bishops.
Theory Snapshot
- 6…h6 7. Bh4 c5 – the main line; Black strikes at d4 while asking the bishop to decide its intentions.
- 6…c5 7. e3 d6 8. Bd3 – a solid system favoured by Karpov.
Illustrative Encounter
Kasparov – Short, Candidates Match 1993 (Game 6)
Kasparov unleashed a devastating kingside attack from the 6.Bg5 line, culminating in a picturesque mating net.
Anecdote
During preparation for the 1993 match, Nigel Short’s team allegedly spent days analysing 6.Bg5 lines—only to learn that Kasparov had different ideas and produced novelties over the board!