Anderssen's Opening is a chess opening defined by the opening move:

:1. a3

Anderssen's Opening is named after chess player Adolf Anderssen, who played it three times in his 1858 match against Paul Morphy. Although Anderssen was defeated decisively in the match, the games he opened with the novelty scored 1½/3 (one win, one loss, one draw).

Anderssen's Opening is not commonly played, and is an irregular opening. The move is classified under the A00 code in the Encyclopaedia of Chess Openings. Anderssen's Opening is also the very first opening enumerated in the Oxford Companion to Chess index of 1327 openings, due to a systematic ordering which begins at White's left-hand and proceeds to White's right-hand .

Themes

Anderssen's Opening does little in the way of development or control of the center, and is rather more of a waiting move. However some players may enjoy the psychological value of such a move, or believe it will help them against an opponent with superior knowledge of opening theory. Usually used by chess players as a form of a joke, or to simply challenge themselves by playing such a move.

Among the more common Black responses to Anderssen's Opening are:

  • 1...d5, which makes a straightforward claim on the center,
  • 1...g6, which prepares to fianchetto the king's bishop to g7,
  • 1...e5, also playable, although White can then play 2.c4 (as occurred in the Morphy-Anderssen match), transposing to a Reversed Sicilian structure where a pawn on a3 may be useful. Another approach is 2.e4 Nf6 3.Nc3, transposing to Mengarini's Opening.

Morphy vs. Anderssen, 1858

During his tour of Tour of Europe and in the Christmastime (December 20-28) of 1858, the American master Paul Morphy engaged Adolf Anderssen in a match held at the Hôtel de Breteuil, Paris. The terms were that the first player to win seven games would be the winner of the match—draws would not count towards a win. The players took turns controlling the white pieces and the black pieces in each game, with Morphy playing as White in the first game. Although Anderssen won the first game in a laborious effort requiring 72 moves and about 7 hours of play, Morphy established dominance by winning three subsequent, shorter games.

Anderssen then employed the opening which came to bear his name in three consecutive games where he controlled the white pieces—the sixth, the eighth, and the tenth. As the match progressed his performance with the opening improved, losing the sixth, drawing the eighth, and finally securing a win in the tenth game. However this proved insufficient to prevent Morphy's win—game and match—in the eleventh. Chess writer Philip W. Sergeant documented the match in a compilation of Morphy's games.

All three games opened identically through their seventh moves. In each the players transposed to a Reversed Sicilian structure, exchanging pawns. White developed his knights, and Black activated his before castling kingside.

Game 6

December 24. Although the players maintained equal exchange of material throughout most of the game, Sergeant noted certain late moves of White's queen and rook as , which allowed Black to bring his material and positional advantage to bear. Using all of his , Black checked with an immediate mating threat, at which point White resigned. In the final position, Black was up a rook.