ECO code: A13
English Opening: Neo-Catalan, 4.b3 c5 5.Bg2 Nc6
The Neo-Catalan variation arises after the moves 1. Nf3 Nf6 2. c4 e6 3. g3 d5 4. b3 c5 5. Bg2 Nc6. Here, White fianchettoes the dark-squared bishop on g2 and supports the center with an early b3, preparing to develop the bishop to b2. Black responds actively with ...c5 and ...Nc6, challenging White's control over the center and aiming for counterplay on the queenside.
Characteristic of this move: The move 4.b3 is a key idea in the Neo-Catalan, aiming to develop the bishop to b2 where it exerts long-range pressure on Black’s central and queenside squares. Black’s ...c5 challenges White's center immediately and helps contest the d4 square indirectly.
Attacking or Defensive: From White’s perspective, this setup is more positional and flexible rather than overtly attacking or purely defensive. White aims to control key central squares and build pressure gradually. Black, by playing ...c5 and ...Nc6, adopts an active stance, seeking counterplay and challenging White’s center.
Center Control: The opening fights indirectly for the center. White does not occupy the center with pawns immediately but controls it with pieces and pressure on key squares. Black tries to challenge this control actively with ...c5 and ...d5.
This opening is defined by the position shown on the board below. The moves displayed are a typical sequence that leads to it, but different sequences can reach the same position and still carry the same opening name.