Author: Paulo Soares
Date: 07:43:00 10/04/99
Go up one level in this thread
On October 04, 1999 at 03:47:40, Ed Schröder wrote: >>Posted by Robert Hyatt on October 03, 1999 at 18:39:17: > >>Most books on tactics define 'sacrifice' as giving up material for some sort >>of compensation (either positional or long term tactical chances). They >>define 'combination' as a sequence of captures resulting in a gain of >>material. >> >>in this game, my material score is always > 0 in the position you give, >>meaning >>that Crafty sees more material coming back to it than it gives up with the >>original rook capture. That seems to better fit a 'combination'. >> >>I will agree that several books talk about 'queen sacrifices' when they are >>not really sacrifices... as giving up a queen to win the opponent's king gets >>more material back than it gives up... >> >>But I like the term 'combination' here... and usually use the term sacrifice >>as in 'sacrificing the exchange'... after the rxc3 bxc3 type sac in many >>Sicilian variations, black is 2 pawns (the exchange) down, yet gets lots >>of compensation for that material, hopefully... Or in sacrificing a pawn >>(such as playing a4-a3 to force your opponent to play bxa3 and end up with >>three isolated pawns that you hope you can eventually win, and which you >>_know_ can not be used to create a passed pawn... >> >>Mainly semantics... But if we call this a sacrifice, then I see one of these >>every 2 games or so... IE QxR RxQ BxR, because after QxR RxQ I am definitely >>down 4 pawns, but after the third move I am up a pawn... >> >> >>Bob > >Then tell me the difference between a "positional sacrifice", and a "sacrifice". > >Anyway here is Jeroen Noomen's view (and analysis of the game in PGN) > >Ed > >---------------------------------------------------------------------------- > > >Rebel Century - GM R. Sherbakov Monthly GM Challenge >--------------------------------------------------------- > >Before the game we decided to go for 1. e4! No more quiet, positional chess, >just open positions and play. Ruslan Sherbakov plays the Sicilian Defence, >the Richter Rauzer variation in particular. Recently I have filled Rebel's >opening book with lots of ideas in this variation, coming from Peter Wells's >excellent book 'The complete Richter Rauzer'. We were not disappointed! > >1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 d6 6. Bg5 e6 7. Qd2 Be7 >8. O-O-O Nxd4 9. Qxd4 O-O 10. f4 Qa5 11. Bc4 Bd7 12. e5 dxe5 13. Qxe5! >(An excellent choice. Everybody plays 13 fxe5, which is objectively stronger. >But that move leads to a slightly better ending for White, and quite dull >positions. Rebel's choice might be less strong from a theoretical point of view, >but for a computer the resulting position is much easier to play. Furthermore, >the queens stay on the board, leaving a lot to play for) >13. ... Qb6 14. Qe2 Qc7?! (A very strange move. I don't know if this has >been played before, but in the afore mentioned book by Peter Wells 14 ... >Rad8 is given, leading to equal play. A game between Karpov and Kamsky - >Buenos Aires 1994 - continued 15 Ne4 Nd5! and Black got excellent >compensation for the sacrificed pawn. Besides, 15 f5? would be bad on >account of 15 .... Qc5! Was Sherbakov afraid of shedding a pawn against a >computer? Maybe.... But his move is clearly wrong, since now Rebel can > >continue....) >15. f5! (... as 15 ... Qc5 is now impossible: 16 Bxf6 wins a piece) 15. >... h6? >(And this is already a big mistake) 16. Rxd7! (Whoops! Clearly not the way >to handle a computer....) 16. ... Qxd7 17. fxe6 Qc7 18. Bxf6 Bxf6 19. Nd5 Bg5+ >20. Kb1 Qd6 21. exf7+ Kh8 22. h4 (White has two pawns for the exchange, a >wonderful bishop on c4, a passed pawn on f7, a giant knight on d5 and also >the black pieces are not cooperating very well. It is clear who has the >advantage here!) >22. ... b5 23. hxg5 bxc4 24. gxh6!! (Fantastic! Rebel sacrifices a knight, >in order to get at the black king) 24. ... Qxd5? (The only way to keep on >playing was to try 24 ... g6 25 Qf3) >25. hxg7+ Kxg7 26. Qg4+ Kf6 27. Rf1+ Ke7 28. Rf5! (This quiet move is the >big point of the knight sac. The rook joins the attack with decisive effect) >28. ... Qe6 29. Qh4+ Kd7 30. Qd4+ Kc7 31. Qc5+ Kb7 32. Qb4+! (A wonderful >queen manoeuvre, after which black is unable to avoid the loss of his queen) >32. ... Kc7 33. Rc5+ Qc6 (Even worse is Kd7 34 Qb7+) 34. Qxc4 Qxc5 35. >Qxc5+ (The >rest is easy. Rebel mops it up without any trouble) 35. ... Kd7 36. c4 Ke6 >37. Qd5+ Kf6 38. Qb7 Kg7 39. c5 Rad8 40. Qxa7 Rxf7 41. Qa4 Rd2 42. Qg4+ Kf8 >43. a4 Rff2 44. Qb4 Ke8 45. g4 Rd1+ 46. Ka2 Rff1 47. c6 Ra1+ >48. Kb3 Rf3+ 49. Kc2 Rf2+ 50. Kd3 and Sherbakov resigned. 1 - 0 > >Congrats to Ed and especially Rebel - of course - for this great >performance. A wonderful game, which I enjoyed very much. And I was pleased >to see that the preparation for this match worked so well. Until next time! > >Jeroen Noomen Excellent game, in which the opening was fundamental. I apologize for insisting in speaking on that, but I was very displeased with the openings that Rebel was playing, mainly against GM Hoffman, and I found difficult that Jeroen Noomen got to solve short term this problem. The one that more leaves me satisfied it is that 13.Qxe5! shows that a theorical inferior move, can be better for a program in a game against a human. I thought that a GM could play a theorical inferior move against a program, obtaining advantage for the type of resulting position, but I never imagined the opposite. I know that it is still early to arrive to definitive conclusions, but what left me more satisfied went the form with that Rebel Team reacted to the adversities. Paulo
This page took 0 seconds to execute
Last modified: Thu, 15 Apr 21 08:11:13 -0700
Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.