1. d2d4  1... g8f6  2. c2c4  2... e7e6  3. b1c3  3... d7d5  4. c4d5  4... e6d5  5. c1g5  5... f8b4 Another recent opening trend, spicing the game a bit compared to the more solid 5...Be7. 6. e2e3  6... h7h6  7. g5f4 A rare move that has been played by Keymer before. 7... c8f5  8. f1d3  8... f5d3  9. d1d3  9... c7c6 Carlsen improves Black's play compared to the earlier Keymer game. 10. g1e2  10... f6h5 [%c_effect h5;square;h5;type;GreatFind;persistent;true] 11. f4e5  11... b8d7  12. h2h3 Creating a retreat route for the bishop. 12... h5f6  13. e5h2  13... e8g8 Carlsen's opening play was a success: the position is equal. Compared to normal Queen's Gambit Declined positions, the light-squared bishops have been exchanged and this clearly favors Black: the position is simplified and the c4-square is weakened after White's typical plan of advancing the pawn minority on the queenside. 14. a2a3  14... b4a5 It's hard to say where the bishop is better placed. Another option was to retreat it to e7. 15. e1g1  15... f8e8  16. a1c1 It's not so clear that the rook is useful on c1. The more natural option is to start the advance of the pawns on the queenside immediately. 16... d8e7  17. b2b4  17... a5d8  18. e2g3 The knignt heads to f5. 18... d8c7  19. g3f5  19... c7h2  20. g1h2  20... e7e6  21. f5g3  21... e6d6 We're not used to Carlsen losing a chess game, let alone in this kind of technical position where he has no problems. 22. h2g1  22... a7a5  23. d3b1  23... d7b6 This looks very good, but Keymer finds a tactical way to simplify the position. 24. b4a5  24... b6c4  25. b1b4 [%c_effect b4;square;b4;type;GreatFind;persistent;true] 25... a8a5  26. c3d5 [%c_effect d5;square;d5;type;GreatFind;persistent;true] A very important resource to avoid a worse position. 26... f6d5  27. b4c4  27... a5a3 Black has a passed b-pawn but White has a mobile center. 28. c4c5 A solid decision, forcing the queen exchange. 28... d6c5 