English Opening: Agincourt Defense, Catalan Defense

1.c4 e6 2.Nf3 d5 3.g3 c5

ECO A13

The English Opening: Agincourt Defense, Catalan Defense is a chess opening line in the English Opening complex, reached after 1.c4 e6 2.Nf3 d5 3.g3 c5.

It is catalogued under code A13 in the Encyclopaedia of Chess Openings (ECO).

The defining move c5 is chosen by Black on move 3.

One named continuation branches from this position: the Semi-Slav Defense.

Named variations

• English Opening: Agincourt Defense, Catalan Defense, Semi-Slav Defense — ECO A13

Study this line with a grandmaster

This position is covered in the Reti Opening course: a GM-authored repertoire you study move by move, then practice against a human-like AI opponent.

Every chess term used here is defined in the chess terms glossary. Browse all opening courses or the full ECO code index.