1. e2e4  1... e7e5  2. g1f3  2... g8f6  3. d2d4  3... f6e4  4. d4e5  4... d7d5  5. b1d2 A line that had a burst of popularity some 10 years ago, mainly thanks to the efforts of the  prominent Azerbaijani GM Vugar Gashimov. 5... e4d2  6. c1d2  6... f8e7  7. f1d3  7... c8g4  8. h2h3  8... g4h5  9. e1g1  9... b8d7  10. g2g4  10... h5g6  11. d3f5 White's key idea. Praggnanandhaa fixes his advantage  on the kingside and is patiently waiting for his opponent to castle there.  11... c7c6  12. d2f4  12... g6f5 Liu decided to castle long as soon as possible.  13. g4f5  13... d8b6  14. d1e2  14... e8c8  15. c2c4  15... d5c4  16. e2c4 Too slow. The arising endgame is slightly better for White. 16... b6b4 Black does not miss his chance. 17. c4b4  17... e7b4  18. f4g3 intending to meet f7-f6 with Bg3-h4, but that also  seems a bit sloppy. 18... b4e7  19. f1e1  19... d7c5 Now Black unwinds and the white pawns, mighty in the middlegame, become weaknesses in the endgame. 20. e1e2  20... d8d5  21. a1c1  21... f7f6  22. g3h4  22... e7d8 Liu is outplaying his opponent, the pawn center is about to  collapse and the remnants will disappear. 23. c1c4 Praggnanandhaa understands that the only way to compensate for the static weaknesses is connected with dynamic play. 23... f6e5  24. c4g4  24... d8f6 Liu has achieved excellent position but in the next few moves misses a strong idea to increase his advantage. 25. f3g5  25... h7h6  26. g5f7  26... h8f8  27. h4f6  27... g7f6  28. f7h6 Praggnanandhaa is almost dry out of the water. 28... d5d7  29. g4g6  29... c5d3  30. e2d2 Now White manages to trade the important enemy rook, and that  means that tables have turned into his favor thanks to the outside passer.  30... d3f4  31. d2d7  31... c8d7  32. g6g7  32... d7c8  33. g1h2 Every tempo counts! 33... f4h5  34. g7h7  34... h5f4  35. h3h4 Here and on the next move, it makes sense to activate  the knight. 35... f8d8  36. h7f7  36... f4h5  37. h6g4  37... d8d4  38. g4f6  38... d4h4 Ufff! This monster is gone! 39. h2g2  39... h5f6  40. f7f6  40... h4f4 It is equal now, but precision is still required by Black. 41. f6f7  41... a7a5 The correct idea. Black needs his queenside pawns advanced to  the max. 42. g2g3  42... c8b8  43. f5f6  43... a5a4  44. f7f8  44... b8a7 