The last round of the regular season for the PRO Chess League was played Wednesday, February 22 on chess.com.
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[Event "Chess.com"]
[Site "Chess.com"]
[Date "2017.02.22"]
[Round "6.1"]
[White "Sturt, Raven"]
[Black "Vovk, Andrey"]
[Result "1-0"]
[ECO "E90"]
[WhiteElo "2389"]
[BlackElo "2630"]
[Annotator "John Upper"]
[PlyCount "73"]
[EventDate "2017.??.??"]
[EventType "team-schev (rapid)"]
[WhiteClock "0:00:15"]
[BlackClock "0:00:46"]
1. d4 Nf6 2. c4 g6 3. Nc3 Bg7 4. e4 d6 5. Nf3 O-O 6. h3 e5 7. d5 {[#] "An
insidious variation" - Kasparov White anticipates that Black will need to play
...f5 or get squashed by White's queenside space advantage, and plays to make .
..f5 as difficult and undesirable as possible.} a5 8. Bg5 {White can go Be3
directly, but hopes to induce ...h6, which will cost Black a tempo when White
plays Qd2, and takes away a square from Black's B, which might go to h6 if
White's DSB leaves that diagonal (e.g. to take on c5).} Na6 9. g4 {Playing
g2-g4 will give White the option of opening the g-file to attack the Black K
if Black goes ...f5. One downside is that White's K is committed to going
queenside, and although White has a natural space advantage there, Black can
play ...c6 and maintain the tension in the center until his Ns and Rs are
ready to open the queenside. White can avoid g2-g4 and castle kingside
instead. If so, White usually plays Nd2, overprotecting e4:} (9. Nd2 Qe8 10.
Be2 Nd7 11. a3 f6 12. Bh4 Nb6 (12... Bh6 13. b4 Nb6 14. Rb1 Bd7 15. Qc2 f5 16.
Qd3 Bxd2+ 17. Qxd2 axb4 18. axb4 $14 {1-0 (34) Vovk,A (2540)-Braun,C (2372)
Cappelle-la-Grande 2012}) 13. b3 Bh6 {One advantage of not getting suckered
into playing ...h6.} 14. Rb1 Nc5 15. O-O {[#]} Bd7 (15... f5 16. b4 axb4 17.
axb4 Nca4 (17... Nxe4 18. Ndxe4 fxe4 19. c5 $1 dxc5 20. bxc5 Na4 21. Nxa4 (21.
Nb5 $1 $16) 21... Qxa4 22. Be7 (22. d6 $1 $16) 22... Rf7 23. d6 $14 {1/2-1/2
(48) Navara,D (2724)-Nakamura,H (2775) Prague 2014}) 18. Nb5 $1 Qd7 19. Qc2 c5
20. Nb3 cxb4 21. c5 dxc5 22. Nxc5 $16 {1-0 (48) Krasenkow,M (2631)-Vovk,A
(2506) Vlissingen, 2009.}) 16. Qc2 f5 17. b4 axb4 18. axb4 Nca4 19. Nb5 Bxb5
20. cxb5 $14 {1-0 (39) Vovk,Y (2571)-Williams,S (2513) Hastings, 2012.}) 9...
Qe8 10. Be2 Nd7 11. Rg1 (11. Qd2 {½-½ (11) Iturrizaga Bonelli,E (2624)
-Demchenko,A (2611) Dresden, 2016.}) 11... Kh8 {[#] Vovk is the top-rated GM
on his team. If Raven had any preparation for the match, he would have looked
at these 3 games:} 12. h4 (12. Nd2 Ndc5 13. Nf1 $6 {hoping to get to g3, but
Black won't allow it.} f6 $5 14. Be3 f5 15. f3 {0-1 (62) To,N (2441)-Vovk,Y
(2561) Vaujany 2010}) (12. Qd2 Ndc5 (12... f6 13. Be3 Qe7 14. h4 f5 15. gxf5
gxf5 16. Bg5 Qf7 $13 {0-1 (77) Van Dongen,C (2342)-Vovk,A (2506) Vlissingen
2009}) 13. h4 (13. O-O-O $5) 13... f5 14. gxf5 gxf5 15. Bh6 Bxh6 16. Qxh6 Qe7
17. h5 Rf6 18. Rg6 $1 Rxg6 19. hxg6 Qg7 $11 20. Qg5 Qxg6 21. Qd8+ Qg8 {Only move.} (21...
Kg7 $4 22. O-O-O $1 $18) 22. Qf6+ Qg7 23. Qd8+ Qg8 {½-½ (23) Batchimeg,T
(2321)-Vovk,Y (2561) Olomouc, 2010.}) 12... f5 13. gxf5 gxf5 14. exf5 Ndc5 15.
Qd2 (15. Nd2 Bxf5) 15... Bxf5 16. Bh6 Bxh6 $1 17. Qxh6 Qe7 18. O-O-O Nb4 $17 {
[#] White has more pawns around his K, but he also has more of his opponent's
pieces in the neighbourhood... with more to come after ...c6.} 19.
Qe3 Nxa2+ $6 {The computer rates this as a terrible mistake -- preferring ...
a4 first --- and during the game commentator GM Max Dlugy wondered if Black
had overlooked the fact that after...} 20. Nxa2 {20 ...Nb3+ is no longer mate.
That's possible, but White's position is not at all easy to play, and that's
without factoring in that this was a 15min + 2 sec rapid game (keep that in
mind when you see a "?" by a move here).} a4 21. Rde1 c6 {With his Bf5, Nc5
and the c-file about to open, Black has a lot of compensation for the piece.}
22. Rg5 cxd5 {[#]} 23. Nd4 (23. cxd5 {and Black has full comp with} Qc7 $1 $13
({or} 23... Rac8 $5)) 23... Be4 $1 {Saves the Bf5 and blocks the e-file,
unpinning the e5-pawn and threatening the Nd4.} 24. Nb5 d4 $40 25. Qg3 (25.
Nxd4 $5 exd4 26. Qxd4+ Qe5 $3 (26... Qf6 $15) 27. Rxe5 Nb3+ 28. Kd1 Bc2+ {Only move.} 29.
Kxc2 Nxd4+ 30. Kc3 dxe5 $19) 25... Qf6 $2 (25... h6 $1 {It looks wrong to
"weaken" the King, but this leaves White with no good place to put his R; e.g.}
26. Rh5 (26. Rg4 Bf5 $19) (26. Rg6 Bxg6 27. Qxg6 Rf6 $19) 26... Nb3+ 27. Kd1
Qh7 {threatening mate on c2,} 28. Rg1 Rg8 29. Qh2 Rxg1+ $18 (29... Bf3 $1 $19))
26. Rg1 $13 Rac8 27. f3 $1 Bc6 28. Kb1 Bd7 $2 29. Nb4 $1 Bxb5 {[#]} 30. cxb5 (
30. Nd5 Qf7 31. Rg7 Qf5+ 32. Ka1 {Only move.} (32. Ka2 $4 d3 $19) 32... Nb3+ 33. Ka2 d3 (
33... Nc1+ 34. Rxc1 $18) 34. Ne7 {Only move.} $18 {wins the Q or forces mate} dxe2 (34...
Qe6 35. Rxh7+ $18) 35. Rg8+ $18) 30... Qf7 31. Rg7 Qf5+ 32. Ka2 $1 (32. Nd3 $1
{also works, based on this line:} Nxd3 33. Rg5 {Only move.} Qf4 34. Bxd3 {Only move.} $18) 32...
Qe6+ {[#]} 33. Bc4 $3 (33. Ka3 $4 Qb3#) (33. Ka1 $2 Nb3+ {Only move.} 34. Kb1 Nd2+ $1 $11
) (33. Nd5 $1 {also successfully decoys the Q:} Qxd5+ 34. Kb1 {Only move.} $18 {as in
the game.}) 33... Qxc4+ (33... Qh6 34. Rg8+ {and mate.}) 34. Kb1 {There are no
safe checks and White threatens Rxh7+ then Qg7#.} Rg8 35. Qg5 {Only move.} {Threatening
Rxh7+ then Qh5#.} Qe6 {So the Q can block along the 6th.} 36. Nd5 {Only move.} h6 37. Nf6
{Only move.} {With two mating threats: Rh7 and Qh6.} (37. Nf6 hxg5 38. Rh7#) 1-0
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