1. e2e4  1... e7e5  2. g1f3  2... g8f6 So noticed that his opponent has thousands of games against 2...Nc6 in the database, but very few with 2...Nf6. \"We had a rest day yesterday and Hans prepares extremely well the openings, so why not the Petroff $6\" 3. f3e5  3... d7d6  4. e5f3  4... f6e4  5. d2d4  5... d6d5  6. f1d3  6... c8f5 Black solves the problem of his most problematic piece. A very good sign for the second player. 7. e1g1  7... f8e7  8. f1e1  8... e8g8  9. b1d2 Main theory so far as expected. 9... e4d6  10. d2f1  10... c7c6  11. c1f4  11... f5d3  12. d1d3  12... b8a6 Looks like the best path for the knight. 13. f1e3  13... a6c7 [#] 14. b2b3 This is a novelty, and a logical one. Niemann prepares the c2-c4 advance, the only realistic chance to put the opponent's center under pressure. 14... c7e6  15. f4e5 So assumed that his opponent's opening preparation ended here. 15... d6e4 A nice maneuver $1 \"Black's only problem is the d5 -pawn.\" 16. c2c4  16... e4f6 \"I thought this equalizes well.\" (So) 17. a1d1  17... g7g6  18. g2g3 Covers the f4 square in advance, and prepares the double trade on f6 and d5. 18... a7a6  19. e1e2  19... f8e8  20. h2h4 A very risky attempt to play for the win. \"I thought this move a blunder because after:\" 20... f6h5 \"his bishop is getting trapped.\" (So) 21. c4d5 Played after more than twenty-three minutes of thought. It was evident that Niemann had missed something. 21... c6d5  22. e3g2 The most natural reaction is not the best one. 22... f7f6  23. e5b8 Same trick here is simply ignored with 23... g8f7 And White has no other choice but to weaken his kingside with 24. g3g4  24... d8b8  25. g4h5  25... e6f4  26. g2f4  26... b8f4  27. h5g6  27... h7g6  28. d1e1  28... e7d6 Now that Black relives the pressure along the d-file, he is clearly better in the endgame. 29. e2e8  29... a8e8  30. e1e8  30... f4g4  31. g1f1  31... f7e8  32. a2a4  32... e8f7 \"I thought the endgame was unpleasant (for White) but it was not clear if was gonna win.\" (So) 33. d3e3  33... d6f4 Missing his best plan, for which So regretted later.