1. d2d4  1... d7d5  2. c2c4  2... e7e6  3. g1f3  3... g8f6  4. g2g3  4... f8e7  5. f1g2  5... e8g8  6. e1g1  6... a7a5 A rare move that has been played a few times by Carlsen. Its greatest merit is to avoid the more theoretical lines, but it's not a useless move since the pawn on a5 is helpful for Black in some variations, either advancing it to a4, as we will see in this game, or else making the a6-square more comfortable for the black bishop after b7-b6. 7. d1c2 A natural reaction. 7... b8c6 Placing the knight in front of the c-pawn in Queen's Pawn structures is always strategically dangerous. 8. a2a3 [%c_effect a3;square;a3;type;GreatFind;persistent;true] Necessary prophylaxis against 8...Nb4.