Chess Opening Theory/1. d4/1...d5/2. c4/2...c6/3. Nf3/3...Nf6/4. Nc3/4...a6

Chebanenko Slav D15 Chameleon Slav, a6 Slav Slav defence 4...a6 · Chebanenko Slav The move 4...a6 introduces the Chebanenko (or Chameleon) Slav. Though it seems a small move, it prepares ideas of ...b5 (either to attack White's c4 pawn or to shore up Black's after ...dxc4) and eases the problems of developing Black's light-squared bishop, as now Qb3 can be met with ...Ra7.Playing the Queen's Gambit Schandorff Lars 2009 Quality Chess UK LLP Glasgow 978-1-906552-18-3 164 The weakening of the b6 square, however, invites White to simply push - /5. c5/ is the most common response, gaining space on the queenside. In the resulting positions, it is very common for Black to fianchetto the dark-squared bishop, where it is a lot more useful by eyeing White's center. Alternatively, White can play /5. e3/, solidifying their d pawn and adding their light-squared bishop to the fight, while accepting 5...b5. Less common are /5. a4/, preventing ...b5, and /5. cxd5/, releasing the central tension but leaving Black to show what purpose ...a6 now serves. History The Chebanenko Slav is named after Vyacheslav Chebanenko, a chess theoretician and mentor who developed the system in the 1970s after facing it against Fyodor Skripchenkohttps://en.chessbase.com/post/the-inventor-of-the-slav-system-with-4-a6https://www.chessgames.com/perl/chessgame?gid=2971400. Theory table 5. c5 Nbd7 6. Bf4 Nh5 + 5. ... Bf5 6. Bf4 Nbd7 + 5. e3 b5 6. b3 Bg4 5. a4 e6 6. Bg5 Nbd7 5. cxd5 cxd5 6. Bf4 Nc6 References