Australian Defense

The Australian Defense is the reply 1...Na6 to 1. d4. The knight goes to the edge of the board, where it controls fewer squares than it would on c6 or f6, and it does nothing immediate to contest the center. The move has one concrete point: it leaves the c-pawn unobstructed. If White continues 2. e4, Black answers 2...c6 and the game enters the De Bruycker line of the Caro-Kann Defense, where the knight is later rerouted from a6 to c7.

That plan depends on White cooperating. Of the three most common second moves, 2. e4, 2. c4 and 2. Nf3, the first is the most frequent, but 2. c4 is close behind and spoils the transposition. After 2. c4 c6 there is no Caro-Kann to reach, and Black is left with a misplaced knight in a Queen's Gambit type of position. For this reason the order 1. d4 c6 is generally a better way to get the same setup. Against 2. e4 Black can still choose 2...Na6, while against 2. c4 the option of a Slav Defense with 2...d5 remains open.

A different and more confrontational treatment appeared when Magnus Carlsen used 1...Na6 against Aleksander Indjic in a Titled Tuesday blitz game in 2025. After 2. c4 he played 2...e5, and following 3. dxe5 he continued 3...d6, giving up a pawn in the manner of the Englund Gambit to open lines for his pieces.

The name comes from Australian practice. The first known Australian game with the move is Kagan versus Wohl from the 1993-94 Australian Championship, which went 2. Nf3 d6 3. e4 c6, with Black again aiming for a Caro-Kann setup supported by ...d6. Alexander Wohl used the line often through the 1990s.

The opening sits in the middle of the popularity rankings for named openings and is uncommon above club level. White scores markedly better than Black in online games. The engine gives White a slight edge and prefers simple central play with e4, Nc3 or Nd2, moves that leave Black's knight with little purpose.