Exchange Variation, Rubinstein Variation

The Rubinstein Variation is the main setup of the Caro-Kann Exchange Variation. With 6. Bf4, White brings the dark-squared bishop out before playing Nf3 or e3, so it stands outside the c3-d4 chain and helps control e5, the square White hopes to use as a knight outpost. The bishop on d3 already covers f5, so Black has to find another role for the c8-bishop.

Black's most popular answer by far is 6...Bg4, which develops the bishop actively and, with the g1-knight still at home, attacks the queen on d1. The usual reply 7. Qb3 moves the queen with gain of time against b7 while adding pressure to d5. Among the alternatives, 6...e6 is a more passive approach and White scores well against it, while 6...g6 aims for a fianchetto and gives Black the best results of the main replies. Engines also rate 6...Qb6 highly, contesting the b-file directly. The position is assessed as roughly balanced, and the play tends to be positional rather than sharp.