How Good Was the Preparation?

Round two of the World Cup continued with many interesting games. The rating favorite did well in most of the games, but there were a couple of exceptions. Sergey Karjakin lost to Alexander Onischuk with the black pieces, and the other surprise was pleasant for the hosts:

[Event "FIDE World Chess Cup"]
[Site "?"]
[Date "2015.09.14"]
[Round "10.25"]
[White "Guseinov, Gadir"]
[Black "Navara, David"]
[Result "1-0"]
[WhiteElo "2634"]
[BlackElo "2728"]
[Annotator "Bojkov, Dejan"]
[PlyCount "101"]
[EventDate "2015.??.??"]
[WhiteClock "0:13:58"]
[BlackClock "0:44:32"]

1. e4 c6 2. d4 d5 3. Nd2 dxe4 4. Nxe4 Bf5 {Diagram [#] Navara's great memory
gives him the advantage of diversity in the opening.} 5. Ng3 Bg6 6. h4 h6 7.
Nf3 Nd7 8. h5 Bh7 9. Bd3 Bxd3 10. Qxd3 e6 11. Bd2 Ngf6 12. O-O-O Be7 13. Ne4 {
This knight is quite a problematic piece in the Caro- Kann for White and
Guseinov hurries to bring in back in the center.} Nxe4 {On the other hand
Black is happy to trade some pieces.} 14. Qxe4 Nf6 15. Qd3 {Diagram [#] A
fighting move.} ({The main line is considered harmless for Black} 15. Qe2 {due
to the maneuver} Qd5 16. c4 Qe4 17. Qxe4 Nxe4 18. Be3 f5 19. Nd2 Nf6 20. Nf3
Bd6 {1/2-1/2 (20) Harikrishna,P (2740)-Berkes,F (2659) Kocaeli 2015}) 15... c5
{A relatively rare move. The main continuations are} (15... O-O) ({and} 15...
Qd5) 16. Kb1 cxd4 17. Nxd4 O-O $6 {What can be more natural than that?!
Instead, both} (17... Rc8) ({and} 17... Qd5 {would be playable.}) 18. Bxh6 $5 {
[%csl Yd8][%cal Rd1d8,Rd3g3] Diagram [#] Kaboom! Something went wrong with
Navara's preparation as this move is not even a novelty! Or maybe he just
considered the complications favourable for him? Judging by the speed with
which he was banging the moves, it should have been the latter.} gxh6 19. Qg3+
Kh8 20. Nxe6 fxe6 21. Rxd8 Raxd8 22. Qe3 Ng8 23. Qxa7 $146 {Diagram [#] Both
players are blitzing, Guseinov comes up with a novelty. The stem game saw} (23.
f4 Rf5 24. g4 Rfd5 25. a3 e5 26. fxe5 {with advantage for White Kokarev,D
(2628)-Gavrilov,A (2456) Moscow 2014}) 23... Bf6 24. f3 {Finally, both players
start thinking. The material balance is weird. A queen and three pawns are
fighting a rook, bishop and knight. Techically speaking we have 9+3=5+3+3.
White should be up a pawn. Concretely speaking, White should be better thanks
to his safe king. However, if Black managed to co-ordinate his pieces, the
evaluation will change as the pieces can easily outnumber the queen in the
attack against the white pawns for instance.} Ne7 (24... Rf7 $5 {looks more
solid.}) 25. Qe3 {Diagram [#] White wins pawn number four but the black rooks
occupy the open files.} Bg7 26. Qxe6 Nd5 27. c3 Rfe8 28. Qf5 {Compy criticizes
this move and suggests instead} (28. Qg6 {presumably to defend the g2 pawn
with the queen. However then Black has} Re2 {and if} 29. Rc1 Nf4 $1 {is
unpleasant for White to say at least.}) 28... Re2 {Creates concrete threats.}
29. Rc1 {Or else Black can sacrifice on c3} (29. g4 Bxc3 {Diagram [#]} (29...
b5) (29... Ne3 {are not bad neither.}) 30. bxc3 Nxc3+ 31. Kc1 Nxa2+ {with
guaranteed draw.}) 29... Rxg2 {Now Navara rejects the draw, possible after} (
29... Ne3 30. Qb5 Rdd2 {[%csl Re8,Yh8][%cal Re8g6,Rg6e8,Rb5e8] Diagram [#]} 31.
Qe8+ Kh7 32. Qg6+ $11) 30. a3 b5 31. Qf7 Nf6 {The position is very complicated.
Navara had other interesting options:} (31... b4 $5 {might lead to a forced
draw (!) after} 32. axb4 Nxb4 33. Qc7 Bf6 34. Re1 Rgd2 35. cxb4 Rxb2+ 36. Kc1
Ra8 37. Re5 $1 {Diagram [#]} Rg2 38. Kb1 Rd8 39. Re1 Ra8 (39... Rb2+ 40. Kc1
Ra8) 40. Re5 Rd8 $11) ({While} 31... Ne3 32. Re1 Nc4 33. Re8+ Rxe8 34. Qxe8+
Kh7 35. Qxb5 {is not that great as the endgame after} Rxb2+ 36. Qxb2 Nxb2 37.
Kxb2 $18 {Diagram [#] is lost for Black. The pawns easily outnumber the bishop.
}) 32. Qb7 Rd5 ({White is better after} 32... Rdd2 33. Qxb5 Nxh5 34. Re1) 33.
f4 $1 {[%csl Gf4] Diagram [#] Surprisingly, Black has problems with the moves
after this. The queen is taking care of everything.} Kh7 34. Re1 {The rook got
active and Black decided to give the b5 pawn but to activate the pieces.} Rdd2
35. Qxb5 Nd5 36. Ka1 $1 {Nice prophylaxis as if White carelessly advances the
pawn} (36. a4 $2 {[%csl Ye1] Diagram [#] there is} Rxb2+ 37. Qxb2 Rxb2+ 38.
Kxb2 Bxc3+ {and Black wins.}) 36... Rgf2 ({Here} 36... Rxb2 $2 {is bad due the
counter-attack} 37. Qd3+ Kh8 38. Re8+ Bf8 39. Qxd5 $18) 37. Qe8 {Diagram [#]
Threatens mate in two.} Nxf4 38. Qe4+ Kh8 39. Qa8+ Kh7 40. Qe4+ Kh8 {Guseinov
made the control moves just in time to get the needed time to find the right
continuation.} 41. Qf5 $1 Rd8 {[%csl Yd8] Diagram [#] Once that the active
black pieces go back, White gets the time he needs to push his queenside pawns.
} 42. Qb5 (42. Qf7 $5 {was not bad neither.}) 42... Rd5 {This makes things
easier for White.} (42... Kh7 {was more stubborn but White is much better
anyway.}) 43. Re8+ Kh7 44. Qc4 {[%csl Rh7][%cal Rc4e4] Diagram [#] The threat
Qc4-e4+ forces the black king out.} Rxh5 45. Qg8+ Kg6 46. Re7 Rh1+ 47. Ka2 Nh5
48. Qe6+ {And the powerful white pieces finished the job.} Nf6 ({Or} 48... Kh7
49. Qe4+) ({Hopeless is} 48... Bf6 49. Qg4+ Bg5 50. Qe4+ Kf6 (50... Rf5 51.
Re6+) 51. Qe6# {Diagram [#]}) 49. Qf7+ Kf5 50. Qxg7 Rhh2 51. Rb7 {Diagram [#]
An epic, irrational battle.} 1-0

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