context: 1. d2d4  1... g8f6  2. c2c4  2... e7e6  3. g1f3  3... d7d5  4. b1c3  4... c7c6  5. c1g5  5... b8d7  6. e2e3  6... d8a5 The Cambridge Springs Variation is a very solid choice. 7. c4d5  7... f6d5  8. a1c1 Nowadays more popular than 8.Qd2. 8... d5c3 The main move and a regular choice of Dreev. 9. b2c3  9... f8a3  10. c1c2  10... c6c5 Keymer is, as usual, very well-prepared and handles the opening well. 11. f1d3  11... c5d4  12. e3d4  12... b7b6  13. d3e4  13... a8b8  14. g5f4  14... c8b7  15. d1e2 An obvious move and a novelty. 15... b7a6 Black wants to swap off the bishops, but on his own terms. 16. e4d3  16... a6d3  17. e2d3  17... b8c8 The opening is a success for Black. He has managed to trade a pair of minor pieces—always a good thing in the ensuing battle with the isolated/hanging pair of pawns. 18. e1g1  18... e8g8  19. c3c4 Carlsen takes the chance to modify the pawn structure to \"hanging pawns.\" From the isolani family, this is considered the most beneficial relative. 19... a3e7 Once again solid and good. The bishop is moving out of the opponent's attack to a better square, protecting the kingside in the process. 20. h2h4 White's play is related to a kingside attack, and this move secures the g5-point for the white pieces. 20... f8d8  21. f1b1  21... a5h5 Swinging over the queen for both defense and counter-actions. 22. b1b5  22... h5g6  23. d3e2 Since he is trying to attack the king, White does not want to trade queens. 23... h7h6 Keymer takes the g5-square away from the white rooks. 24. a2a4  24... g6g4 This was Keymer's plan. He is now looking for nice central counter-strikes. 25. g2g3  25... a7a6 Preparing the coming sacrifice. 26. b5b2 Deep prophylaxis, so typical for Carlsen, no matter what the time control is. 26... e7h4 Things are starting to heat up and Keymer is standing strong. 27. a4a5 The pawn on h4 is not so important for White, who is betting on his c-passer. 27... b6a5 There is not much of a choice. 28. c4c5  28... h4g5 Once again very accurate play by the German GM. The white bishop is too important for the support of the c-pawn. 29. c5c6  29... g5f4  30. c6d7  30... c8c2  31. b2c2  31... f4g3 Keymer does not slow down $1 32. f2g3  32... g4g3  33. g1f1  33... d8d7 The strongest of the white pawns is gone and he is left with just one last pawn that can provide any winning hopes. 34. c2c8  34... g8h7  35. e2e4  35... g3g6 Life looks easier without the queens. 36. e4g6  36... f7g6  37. f1e2 Carlsen has at least managed to somewhat ruin his opponent's pawn structure. The a-passers are doomed, but does this mean that Carlsen has any winning chances $2 After all, all that Keymer needs to do to draw is to trade his six ( $1) pawns for the remaining white pawn. 37... g6g5  38. e2e3 White hurries to protect his precious pawn. 38... d7d6  39. f3e5  39... a5a4  40. e3e4  40... a6a5  41. c8c4  41... d6a6  42. c4a4  42... h7g8 A step in the wrong direction.