O'Kelly Variation, Normal System, Taimanov Line

The Taimanov Line is Black's most direct treatment of the Normal System. Black does not insert 4...Nf6 5. Nc3 before ...e5. Instead the e-pawn advances at once and hits the centralized knight. Because 2...a6 has already covered b5, the knight cannot use that square and must retreat or go to f5. Black gains a tempo, fixes a pawn on e5 and fights for d4, but accepts the familiar ...e5 drawbacks: a backward d-pawn and a hole on d5. Since White has not yet committed the queen's knight to c3, White keeps more freedom in how to arrange the pieces, and the pin with ...Bb4 is not yet available to Black.

White usually retreats with 5. Nf3, chosen in about half of games, though Black scores well against it. The retreat 5. Nb3 is the engine's first choice and gives White the best results in practice. The more active 5. Nf5 is also common. The engine rates the position as roughly balanced, and in online games Black wins slightly more often than White.