1. d4 Nf6 2. Bg5!? Although immensely popular at the club level, the Trompovsky is still seen as some sort of offbeat opening that is seldom employed by the top class. However, Shakhriyar Mamedyarov is an imaginative player who is always seeking for original positions to exersize his talent.
2... Ne4 3. Bf4 c5 4. f3 Nf6 5. dxc5 b6 6. e4 Grabbing a pawn with 6. cxb6 Qxb6 7. Qc1 d5 allows Black to build a massive center (next Nc6 and e5) while White is experiencing serious problems with completing the development.
6... bxc5 7. e5!? One of the most persistent Trompovsky devotees, GM Julien Hodgson, preferred different scheme with 7. Nc3 Nc6 8. Bc4
7... Ng8!? "Undeveloping" the Knight, but still probably better than 7...Nh5 8. Be3 which leaves this piece a bit strained. Of course, it can be said that White "over-extended" his center and that e5 might be an object of attack for Black to gain tempi while continuing development. 7...Qc7!? deserves serious consideration.
8. Nc3 Nc6 9. Bb5!? The Knight on c6 was ready to join forces with other Black pieces in putting a pressure on e5, so White wants to have an eye on it in case of an exchange being necessary.
9... Nd4 Forgeting about e5 for the moment, the prospect of "winning" a pair of Bishops is too tempting to resist.
10. Nge2!? Mamedyarov prefers to get another piece into the play. 10. Bc4 e6 is also reasonable, but it will be somewhat easier for Black to create counterplay down the b-file.
10... Nxb5 11. Nxb5 Qa5+ Black was probably hoping for 12. Nbc3 Rb8...
12. Nec3!? a6 13. Nd6+!? You don't have to ask Mamedyarov twice! 13. Na3 with idea 14. Nc4 is objectively better, but where is the fun in it? Black is about to face serious problems with his King left in the center and under the heavy fire of White heavy pieces. Pawn d6 is "cutting the board in two", one of the favorite motifs of famous attacker GM Larry Christiansen, hindering the co-ordination between Black's defences.
13... exd6 14. exd6 Qb4 With hindsight, it might have been better to play Bb7 immediately and then rush with the King to c8, while Queen could retreat to d8 should White give a check on e8.
15. Qe2+ Kd8 16. Bd2! White is not bothered to move the Bishop backwards and leave d6 pawn unprotected. The potential discovered attack on Qb4 will have a greater effect.
16... Bb7 Unfortunately, it was not possible to snatch a pawn 16... Bxd6 17. Ne4 Qb6 (17... Qxb2 18. Bc3 Qa3 19. Bxg7)
18. Nxd6 Qxd6 19. Ba5+
17. O-O-O?! Actually, 17. Nd5! would have been a final assault, because the Queen cannot protect a5 and run away from White pieces at the same time 17... Qb5 18. c4 Qa4 19. b3 Qa3 20. Nc3! with idea Nb1 which is either winning a Queen or checkmates with Ba5+
17... Nf6 18. Rhe1 Bxd6? And just as White let him off the hook, Black cracked. It was a final moment to get away from the Bd2 rentgen. Obviously, pawn on d6 made him a lot more nervous. 18... Qb6 was the only move.
19. Ne4! Bf4 Too late for 19... Qb6 20. Nxd6 Qxd6 21. Ba5+ Now everything is forced...
20. Bxf4 Nxe4 21. fxe4 Re8 22. Qg4! Re6 23. Qxg7 Bc6 24. Qf8+ Re8 25. Qxf7 even without direct threats at the moment, Black has realised that his King cannot escape and simply threw the towel.