Semi-Averbakh System

The Semi-Averbakh System is a relative of the Averbakh Variation, classified under ECO E73, and both bear the name of Yuri Averbakh. After 5. Be2 O-O White places the dark-squared bishop on e3 instead of g5. The bishop does less to restrain Black's central break than it does from g5, but it covers d4 and the queenside dark squares, and White keeps open the choice between Nf3, Nge2 or a later f-pawn advance. Without f3 or a knight on f3, the bishop on e3 has no protection from ...Ng4, a resource Black can use to gain the bishop pair or tempi.

The most frequent reply is 6...e5, staking the usual King's Indian claim in the center. The second most popular, 6...Nbd7, prepares the same break, while 6...Nc6 puts pressure on d4 at once and has scored well for Black in practice. Engines prefer 6...Nc6, 6...Na6 and 6...c6, and they give White a slight edge. The line sits in the middle tier of popularity, and results in online games favor White slightly.