After brief hesitation Black opts for the attack.
1. e2e4  1... e7e5  2. g1f3  2... b8c6  3. f1b5  3... a7a6  4. b5a4  4... g8f6  5. e1g1  5... f6e4 Definitely not a surprise by Mamedyarov. The Open Ruy Lopez was his bread and butter long before he reached Niemann's age. 6. d2d4  6... b7b5  7. a4b3  7... d7d5  8. d4e5  8... c8e6  9. b1d2  9... e4c5  10. d1e2 And Niemann chooses a rare continuation in order to avoid the Azeri's heavy preparation. 10... g7g6  Taken by surprise Mamedyarov chooses \"an interesting sideline,\" at least according to Chessbase. 11. c2c3 The most logical reply, and some thought. 11... f8g7 That's the point, but White is not too concerned about the pawn. 12. f3d4  12... c6e5  13. f2f4 The game has been opened in White's favor, and Niemann launches a nasty attack against the black king. 13... e5d3  14. f4f5 Anand, who was annotating for the official site, could not hide his amazement about Mamedyarov's opening choice. White has more than enough compensation for the pawn. 14... d3c1 Black was also burning time on his clock. 15. a1c1  15... g6f5  16. d4f5  16... g7f6 Aaaand, this is a novelty $1 But it is very likely that neither player was aware of it. 17. b3c2 Niemann's desire to keep this piece alive is perfectly understandable. With the bishop on the b1-h7 diagonal, Black can never even think about castling short. 17... c5d7  18. f5d4 All of this looks logical, but actually releases the tension. 18... d8e7 Taking half a breath. 19. c1e1 This piece also stood too well to be moved. 19... f6d4  20. c3d4  20... e8c8 The king escaped the guillotine, and it is anyone's game. 21. d2b3  21... e7d6  22. a2a4  22... b5a4 White might have underestimated this. 23. b3a5  23... d6b6 A double attack. The next moves are more or less forced. 24. e2d2  24... d8g8  25. c2a4  25... g8g4 Both players are on the attack. 26. a5c6 As obvious as this move is, it is not optimal. The knight is too valuable to be traded easily. 26... d7b8 That's the problem. White loses his stability and has to follow a forced sequence: 27. h2h3  27... b8c6 The best move. Mamedyarov wins two pawns for the exchange and opens all the windows into the enemy king's castle. 28. h3g4 