Rubinstein System, Taimanov Variation

The Taimanov Variation is named after Mark Taimanov. It answers 4. e3 with 4...Nc6, developing the queen's knight before the c-pawn has moved. The knight eyes d4 and e5, but it blocks the ...c5 break that Black uses in other Rubinstein lines. The most frequent replies are 5. Nf3, 5. Bd2 and 5. Bd3. The variation is a rarely played sideline. The engine gives White a slight edge, and White scores well in practice.