Catalan Opening: Open Defense

1.d4 Nf6 2.c4 e6 3.g3 d5 4.Bg2

ECO E01

The Catalan Opening: Open Defense is a chess opening line in the Catalan Opening complex, reached after 1.d4 Nf6 2.c4 e6 3.g3 d5 4.Bg2.

It is catalogued under code E01 in the Encyclopaedia of Chess Openings (ECO).

The defining move Bg2 is chosen by White on move 4.

3 named continuations branch from this position, including the Alekhine Variation and the Modern Sharp Variation.

Named variations

• Catalan Opening: Open Defense, Alekhine Variation — ECO E03
• Catalan Opening: Open Defense, Modern Sharp Variation — ECO E04
• Catalan Opening: Open Defense, Classical Line — ECO E05

Study this line with a grandmaster

This position is covered in the Nimzo-Indian Defense 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.