1. d2d4  1... g8f6  2. c2c4  2... e7e6  3. g1f3  3... d7d5  4. g2g3 The choice of the Catalan Opening shows how seriously Carlsen was taking this match. That was his main opening in the world championship duel against Nepomniachtchi. 4... f8e7  5. f1g2  5... e8g8  6. e1g1  6... d5c4  7. d1c2  7... a7a6  8. a2a4  8... c8d7  9. c2c4  9... d7c6  10. c1g5 This is one of the most important positions in the Catalan. 10... a6a5 A rare move in Nakamura's games. The two most popular alternatives, 10...Bd5 and 10...Nbd7, had already been tried by him. 11. b1c3  11... b8d7 