Orthodox Variation, Positional Defense, Closed Line

The Closed Line is White's most popular answer to the Positional Defense. With 8. d5 White gains space and locks the center, which removes the tension that ...Nbd7 was meant to support. The knight on d7 then needs a new role. The usual choice is 8...Nc5, played in nearly half the games, which puts the knight on an active square and pressures e4. The second option, 8...a5, takes control of b4 and so makes it harder for White to dislodge a knight from c5 by advancing the b-pawn. A smaller group of games continue 8...Ne8, clearing the f-pawn for an early ...f5. Engines also consider 8...Qe7.

The resulting structure follows the familiar closed King's Indian pattern. White expands on the queenside, aiming at c5 and the c-file, while Black prepares ...f5 and plays on the kingside. Engines rate the position roughly balanced. In Lichess games Black scores slightly better than White, and draws are uncommon, which reflects how sharp and double-edged these races tend to be.