Two Knights Defense

Two Knights Defense

a b c d e f g h 8 8 7 7 6 6 5 5 4 4 3 3 2 2 1 1 a b c d e f g h
Moves	1.e4 e5 2.Nf3 Nc6 3.Bc4 Nf6
ECO	C55–C59
Origin	Late 16th century
Parent	Italian Game

The Two Knights Defense (also called the Prussian Defense) is a chess opening that begins with the moves:

1. e4 e5

2. Nf3 Nc6

3. Bc4 Nf6

First recorded by Giulio Cesare Polerio^[1] (c. 1550 – c. 1610) in the late 16th century, this line of the Italian Game was extensively developed in the 19th century. Black's third move is a more aggressive defense than the Giuoco Piano (3...Bc5). Black allows White to attack his f7-pawn with 4.Ng5. If White does so, the game quickly takes on a tactical character: Black is practically forced to give up a pawn for the initiative. The complications are such that David Bronstein suggested that the term "defense" does not fit, and that the name "Chigorin Counterattack" would be more appropriate.^[2] The Two Knights has been adopted as Black by many aggressive players including Mikhail Chigorin and Paul Keres, and world champions Mikhail Tal and Boris Spassky. In modern grandmaster play, 3.Bc4 is less common than 3.Bb5, and the more solid 3...Bc5 is the most frequent reply, so the Two Knights Defense is infrequently seen. It remains popular with amateur players. The theory of this opening has been explored extensively in correspondence chess by players such as Hans Berliner and Yakov Estrin.