The Queen's Knight Defense (also known as the Nimzowitsch Queen Pawn Defense, Bogoljubov–Mikenas Defense, or Lundin Defense) is a

chess opening The opening is the initial stage of a chess game. It usually consists of established Chess_theory#Opening_theory, theory. The other phases are the chess middlegame, middlegame and the chess endgame, endgame. Many opening sequences, known as ''op ...

defined by the moves: : 1. d4 Nc6 Unless the game transposes to another opening, the '' Encyclopedia of Chess Openings'' code for the Queen's Knight Defense is A40.

Discussion

This opening was tried by some hypermodern players such as

Aron Nimzowitsch Aron Nimzowitsch (; , ''Aron Isayevich Nimtsovich''; 7 November 1886 – 16 March 1935) was a Latvian-born Danish chess player and writer. In the late 1920s, Nimzowitsch was one of the best chess players in the world. He was the foremost f ...

and Efim Bogoljubov, but it has never become very popular. The move 1...Nc6 is a fairly committal move which blocks Black's c-pawn; usually Black delays playing it until White's setup is clear. Most games featuring 1.d4 Nc6

transpose In linear algebra, the transpose of a Matrix (mathematics), matrix is an operator which flips a matrix over its diagonal; that is, it switches the row and column indices of the matrix by producing another matrix, often denoted by (among other ...

to other openings. After 2.e4 the

Nimzowitsch Defense The Nimzowitsch Defence (named after Aron Nimzowitsch) is a somewhat uncommon chess opening characterised by the moves: :1. e4 Nc6 This opening is an example of a hypermodern opening in which Black invites White to occupy the of the board ...

arises. After 2.Nf3 d5 a variation of the

Queen's Pawn Game The Queen's Pawn Game is any chess opening starting with the move: : 1. d4 It is the second-most popular opening move after 1.e4 (King's Pawn Game). Terminology The term "Queen's Pawn Game" is usually used to describe openings beginning wit ...

is possible. After 2.c4 d5 the opening is a

Chigorin Defense The Chigorin Defense is a chess opening named for 19th-century Russian master Mikhail Chigorin. An uncommonly played defense to the Queen's Gambit, it begins with the following moves: :1. d4 d5 :2. c4 Nc6 The Chigorin Defense violates seve ...

. There are some lines that are unique to 1.d4 Nc6, most importantly 2.d5 which chases the knight away, usually to e5. The opening resembles an Alekhine's Defence but on the opposite side of the board. In an opening book by Sid Pickard, this variation was called the Bozo-Indian Defense ("Bozo" being a combination of the prefixes "Nimzo" and "Bogo"). The Queen's Knight Defense was featured (although not mentioned by name) in the season four episode of ''Chuck'' entitled " Chuck Versus the Family Volkoff".

Transpositions

After 1.d4 Nc6 Black should be ready for various continuations; however, White cannot just ignore the fact that his opponent is ready to play ...e5 in the next move. Therefore, practically speaking, White is more likely to limit himself to the move 2.Nf3, trying to reach a position where he has a theoretical advantage. Black could respond to Nf3 with two main moves: *2...d6 can transpose to the Pirc Defense (if Black successfully plays d6 and g6, White must play e4 and go into open games theory) or the King's Indian Defence if White plays an early c4 and goes into closed games theory. Unusual sequences after 2.Nf3 d6: **

Dutch Defence The Dutch Defence is a chess opening characterised by the moves: : 1. d4 f5 Black's 1...f5 stakes a claim to the e4-square and envisions an attack in the middlegame on White's ; however, it also weakens Black's kingside to some extent, espec ...

– 3.g3 g6 4.Bg2 Bg7 5.0-0 f5 6.d5 ** Ruy Lopez – 3.e4 e5 4.Bb5 exd4 5.Qxd4 *2...e6 can transpose to the Nimzo-Indian Defence, Bogo-Indian Defence and the

if White plays c4 immediately. If White tries going for an open game, the game can transpose to a Guimard French or another French line with 4...e5, or the Nimzowitsch Defence.

Illustrative games

Erich Weinitschke vs. Efim Bogoljubov, Bad Elster, Germany, 1938
nalysis by Sid Pickard

Notes

References

* * * {{cite book , author= Sid Pickard , year=2001 , title=The Bozo-Indian Defense , publisher=ChessCentral , url-access=registration , url=https://www.chesscentral.com/the-bozo-indian-defense-chess-opening-e-book-download/ Chess openings