Zurich Rd1: Caruana errs, Nakamura wins!

[Event "4th Zurich CC Classical"] [Site "Zurich SUI"] [Date "2015.02.14"] [Round "1"] [White "Caruana, F."] [Black "Nakamura, H."] [Result "0-1"] [ECO "B90"] [WhiteElo "2811"] [BlackElo "2776"] [Annotator "Ramirez Alvarez,Alejandro"] [PlyCount "82"] [EventDate "2015.02.14"] 1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 a6 6. h3 e5 7. Nde2 h5 {The evolution of chess. The move h5 helps defend d5 by preventing g4-g5. Not something that is easy to explain to an amateur, and it looks like it is going against every opening principle out there, but that is the Najdorf for you.} 8. g3 Nbd7 9. Bg5 Be7 10. a4 Nc5 11. Bg2 Be6 12. a5 {White has a nice bind on both d5 and b6, which means that Black will have to break out of it with a sub-optimal pawn push.} b5 (12... Nfxe4 {Is an interesting tactical solution, but it falls short.} 13. Nxe4 Bxg5 14. Nxg5 $1 Qxg5 15. b4 $1 Nd7 16. Qxd6 { doesn't look good for Black; notice how active the bishop on g2 has become.}) 13. axb6 Qxb6 14. b3 O-O 15. O-O a5 16. Qd2 {Caruana's position seems to be slightly more pleasant. He has some pressure against d6 which is more valuable than Black's potential pressure on the queenside once he breaks with a4.} Rfc8 17. Rfd1 a4 $5 {The pawn sacrifice clears the c4 square for the bishop and gives Black real targets on the queenside. However it is not immediately obvious how Nakamura will recover this pawn.} (17... Ra6 {was more passive, simply defending the d6 pawn, but was also playable.}) 18. bxa4 Bc4 19. a5 $1 { A nice solution; the pawn is still untouchable.} Qd8 (19... Rxa5 20. Bxf6 $1 ( 20. Nd5 {immediately doesn't work} Nxd5 21. Rxa5 Bxg5 {and the queen cannot recover material without losing the defense of the a5 rook.}) 20... Rxa1 (20... Bxf6 21. Nd5 Bxd5 22. Qxa5 $16 {wins an exchange.})) 20. Bxf6 Bxf6 21. Qxd6 Qxd6 22. Rxd6 Nb7 23. Rd2 Rxa5 24. Rb1 Nc5 {Black is still down a pawn, but he retains compensation. His pieces are active, White's are slightly awkward.} 25. Nd5 Bd8 26. h4 Ra3 27. Nec3 Rca8 28. Rdd1 Ba5 29. Nb5 {steadiyl White has made progress; his knights are in better squares, Black has not created any immediate threats.} Ra2 30. Bf3 g6 31. Ne7+ (31. Nd6 $1 Bxd5 32. Rxd5 Rxc2 33. Ra1 $1 {This nice detail would have led to a position whre only White can win. Black has great chances to hold the position, but with e5 hanging and some pressure dowdn the a-file it is not an easy practical task.}) 31... Kg7 32. Nc6 Na4 33. Nd6 Be6 34. Rb7 (34. Nxa5 Rxa5 35. Rd2 Rc5 $11) 34... Rxc2 35. Nxe5 $6 (35. Nxf7 $1 {This pawn was more valuable and White could have taken it without problems. For example:} Bxf7 (35... Nc5 $8 36. Rb5 $1 {attacking on a5 saves the f7 knight.} Bxf7 37. Rxa5 Rxa5 38. Nxa5 {and White is far from a win, but he can push forever.}) 36. Nxe5 Rf8 37. Rdd7 $18) 35... Nc5 $1 36. Re7 { The problem with Caruana's solution is that this rook on e7 starts to feel very uncomfortable as it is running out of squares.} Kf8 37. Nc6 $6 (37. Rxe6 Nxe6 38. Ndxf7 Bc3 39. Nh8 $1 $13) 37... Nb3 {Suddenly Black has a real threat: Bb6 is coming! Also the knight on c6 is currently hanging.} 38. e5 Bb6 $17 39. Rb7 $2 (39. Rxe6 $1 fxe6 (39... Bxf2+ 40. Kh1 fxe6 41. Nb4 $14 {and now it is Black's rook that feels uncomfortable. Well, both of them, as a8 and c2 are hanging.}) 40. Nd4 $1 Bxd4 41. Bxa8 Bxf2+ 42. Kg2 Bd4+ 43. Kh3 Bxe5 {and Black is better, obviously, but very far from winning.}) (39. Nd4 Nxd4 40. Bxa8 { leaves the rook on e7 unprotected, which is why 39.Rxe6 is good.}) 39... Bxf2+ 40. Kg2 $2 (40. Kh1 Bxg3 {is winning for Black too}) 40... Bc5+ 41. Kh1 Raa2 { and now it is very obvious that Black has nowhere near a perpetuatl and Black will checkmate on h2.} 0-1

[Event "4th Zurich CC Classical"] [Site "Zurich SUI"] [Date "2015.02.14"] [Round "1"] [White "Aronian, L."] [Black "Karjakin, Sergey"] [Result "1/2-1/2"] [ECO "D47"] [WhiteElo "2777"] [BlackElo "2760"] [Annotator "Ramirez Alvarez,Alejandro"] [PlyCount "53"] [EventDate "2015.02.14"] 1. d4 Nf6 2. c4 e6 3. Nf3 d5 4. Nc3 c6 5. e3 Nbd7 6. Bd3 dxc4 7. Bxc4 b5 8. Bd3 Bb7 9. e4 b4 10. Na4 c5 11. e5 Nd5 12. dxc5 Nxc5 13. Nxc5 Bxc5 14. O-O (14. Bb5+ Kf8 {has been considered acceptable for Black for quite some time now.}) 14... Be7 $5 {A new move in a well-known position. 14...h6 is very popular and has been played by Aronian himself as black.} 15. Qe2 Qb6 16. Ng5 h6 17. Ne4 Rd8 18. Qf3 {It is logical to add pressure on the kingside as it is the only place where White can hope to start an initiative.} Ba6 19. Rd1 O-O 20. Qg3 Kh8 (20... Bxd3 $2 21. Bxh6 $18) 21. Qh3 Kg8 $2 (21... Bxd3 22. Rxd3 Kh7 23. Rg3 { looks scary for Black, but is probably nothing} Qd4 $1 24. Rxg7+ Kxg7 25. Bxh6+ Kg6 26. Bxf8 Rxf8 27. Qg4+ $11) 22. Bxh6 $1 gxh6 23. Qxh6 f5 24. Qg6+ Kh8 25. Qh6+ Kg8 26. Qg6+ Kh8 27. Qh6+ {And the worst mistake of all: agree to a draw!} (27. Qh6+ Kg8 28. Qg6+ Kh8 29. Ng3 $1 {Black has to deal with a couple of threats. The most immediate of them is Ng5, which checkmates Black.} Bc5 $8 ( 29... Rd7 30. Qh6+ $1 Kg8 31. Bxa6 Qxa6 32. Rxd5 $1 Rxd5 33. Qg6+ Kh8 34. Nh5 $18 {Any time that Black defends on g8 with a rook he allows Qh6 checkmate.}) 30. Qh6+ Kg8 31. Nh5 Bxf2+ 32. Kh1 Qc7 33. Qxe6+ Qf7 34. Qxf7+ Kxf7 35. Bxa6 { and with two extra pawns White has some real winning chances. It's still a long way to go as Black is rather active, but it is clear that Aronian would prefer this position than drawing. It is unclear what he missed.}) 1/2-1/2