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8 a8 rd b8 c8 bd d8 qd e8 kd f8 bd g8 nd h8 rd 8
7 a7 pd b7 pd c7 pd d7 pd e7 pd f7 pd g7 pd h7 pd 7
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2 a2 pl b2 pl c2 pl d2 e2 pl f2 pl g2 pl h2 pl 2
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1. d4 Nc6

The Queen's Knight Defense (also Nimzowitsch's Queen Pawn Defense or Bogoljubov-Mikėnas Defense) is a variation on the Queen's Pawn Game, and is classified under ECO code A40. The opening moves are:

  1. d4 Nc6

Due to the committal nature of this opening, it is often frowned upon and in any event unpopular at master level. However, it has some credibility in being able to transpose to other openings whilst limiting white's options.


The Queen's Knight Defense was first studied by hyper-modern masters Aron Nimzowitsch and Efin Boguljobuv, but they both concluded that its unique lines were not viable, and that the only benefit it served was as an alternative way to approach several other defensive set-ups (see **Transpositions** below).

Main Line[]

The main non-transpositional line begins with the move 2. d5, attacking the knight. Black then escapes with Ne5, and white can secure a strong central position with 3. e4. This opening is a mirrored Alekhine's Defence, but is considered less sound as the queen is already defending white's pawn.

Montevideo Retreat[]

In response to 2. d5, black instead retreats with Nb8, the Montevideo retreat. This outstanding move prevents black from having made any progress on their first two turns, and is only slightly compensated because they have tricked white into over-extending.

Lithuanian Variation[]

Instead of d5, white may initially respond 2. c4, in which case black should play e5, threatening the d-pawn. White then responds with 3. d5, moving it out of danger and threatening the knight, but with added protection from the c-pawn. Black then escapes the knight with Nce7. This offers white rapid queenside development, whilst black has largely caged themself in.

Cannstatter Variation[]

The same as the Lithuanian, but instead of 3... Nce7, black plays Nd4 in order to avoid trapping themself. However, both Nf6 and e3 kick the knight, leaving white with a decisive advantage.

On the whole, none of these unique lines are strategically beneficial to black, nor do they hold any particular traps.


Transpositions are the most common benefit of this opening.

2. e4 transposes to the Nimzowitsch Defense, ECO Code B00.

2. c4 d5 transposes to the Queen's Pawn Game, Chigorin Defense, ECO Code D07.

2. Nf3 d5 transposes to the Queen's Pawn Game, Zukertort Variation, ECO Code D02.