Agincourt Defense, Catalan Defense Accepted

This position, also known as the Neo-Catalan Accepted, arises when Black answers White's kingside fianchetto by taking the c4-pawn instead of maintaining the pawn on d5 with ...Be7. The capture opens the long diagonal for the bishop on g2 and gives up central presence. In return, White must spend time recovering the pawn, and Black gains a tempo or two to complete development with ...c5 or ...c6 and queenside expansion. White has not committed the d-pawn, and 5. d4 transposes directly into the Open Defense of the Catalan Opening.

The most frequent reply is 5. O-O, which postpones the recapture in favor of development and relies on the pressure along the diagonal to win the pawn back later. 5. Qa4+ regains it immediately, usually after 5...Nbd7 or 5...c6 followed by 6. Qxc4, leaving White with a comfortable, slightly freer game. 5. Na3 is a rarer way to target c4 with the knight. The engine considers the position roughly balanced, while White scores well in practice.