Both players are entering one of the most complex structures, a Carlsbad with a white dark-squared bishop behind the pawn chain. So far they are following the game So-Mamedyarov that was played a few days ago.
1. d2d4  1... g8f6  2. c2c4  2... e7e6  3. b1c3  3... f8b4  4. e2e3  4... e8g8  5. f1d3  5... d7d5  6. c4d5  6... e6d5  7. a2a3 A trendy line of late. 7... b4d6 