A step in the wrong direction.
1. d2d4  1... g8f6  2. c2c4  2... g7g6  3. g2g3  3... f8g7  4. f1g2 The Fianchetto system has a very  solid reputation against both the Grunfeld and the King's Indian Defenses.  4... e8g8  5. b1c3  5... d7d6  6. g1f3  6... b8c6  7. e1g1  7... e7e5  8. d4d5 This was also Carlsen's choice when playing against the World in 2010. 8... c6e7  9. e2e4  9... b7b6  10. a1b1  10... a7a5  11. f1e1 A solid, prophylactic move, \E0 la Petrosian. 11... f6d7  12. a2a3 Yes, this will be played sooner or later. 12... h7h6  13. f3h4 Ding's beloved maneuver, which was invented by the prominent  GM Mark Taimanov. It is pure prophylaxis: White wants to tame the kingside pawns of the opponent and is ready to put pressure against the f5 pawn  whenever it is advanced. 13... f7f5  14. e4f5  14... g6f5  15. d1c2 Following the  idea. The f5 pawn is under pressure and none of the duo is risking to make a step further. Notice too that the advance of the black h-pawn weakened  the g6 square and Black can no longer use it for his knight. 15... d7f6  16. b2b4 The kingside is blocked and White resumes his queenside assault. 16... c8d7  17. c4c5  17... a5b4  18. a3b4  18... e5e4 Carlsen risks, but now the game is  opened in his opponent's favor. 19. c5c6  19... d7e8  20. f2f3 Of course! Black is not prepared for the opening of  the game. 20... f6d5  21. c3d5  21... e7d5  22. f3e4  22... f5e4  23. g2e4 The only little slip of the Chinese GM in the game. 