Ciric-Nezhmetdinov

[JWorcester]

[D] r2Bkb1r/2p2p2/p1np4/1p2p2b/3PPnpN/2P4P/PP2QP2/RN3RK1 w kq -

I've been going over this game and the question is whether black is winning as a result of the queen sac. In all the lines I'm examining it appears so. However the horizon effect is quite apparent with this position.

Anyone care to run this through a really fast machine and see if black's sacrifice is completely winning or if there is a line that saves white?

Cheers.


[Event "Rostov on Don"]
[Site "Rostov on Don"]
[Date "1961.??.??"]
[Round "8"]
[White "Ciric, Dragoljub M"]
[Black "Nezhmetdinov, Rashid"]
[ECO "C79"]
[Result "0-1"]

1. e4 e5 2. Nf3 Nc6 3. Bb5 a6 4. Ba4 d6 5. O-O Bg4 6. h3
Bh5 7. c3 Nf6 8. Qe2 g5 9. g4 b5 10. Bb3 Bg6 11. d4 h5
12. Bxg5 hxg4 13. Nh4 Bh5 14. Bd5 Nxd5 15. Bxd8 Nf4 [Diagram above] 16. Qe3
Nxh3+ 17. Kg2 Nf4+ 18. Qxf4 exf4 19. Bg5 Be7 20. Bxe7 Nxe7
21. Nd2 Kd7 22. Rh1 f6 23. b3 Bf7 24. d5 Rh6 25. Rh2 Rah8
26. Rah1 Nxd5 27. exd5 Bxd5+ 28. f3 g3 0-1

[Jack Lad]

http://www.chessgames.com/perl/chessgame?gid=1451715
After 16. Qc2 white is better but black can force a draw with Nxh3+.
[d] r2Bkb1r/2p2p2/p1np4/1p2p2b/3PP1pN/2P4n/PPQ2P2/RN3RK1 w kq - 0 17

In the game white had no good reason to give the queen back as 18. Kg3 instead seems to be winning.
[d] r2Bkb1r/2p2p2/p1np4/1p2p2b/3PPnpN/2P1Q3/PP3PK1/RN3R2 w kq - 2 18

[zullil]

[D] r2Bkb1r/2p2p2/p1np4/1p2p2b/3PPnpN/2P4P/PP2QP2/RN3RK1 w kq -

Anyone care to run this through a really fast machine and see if black's sacrifice is completely winning or if there is a line that saves white?

Stockfish sees a draw:

Code: Select all

Searching: r2Bkb1r/2p2p2/p1np4/1p2p2b/3PPnpN/2P4P/PP2QP2/RN3RK1/ w kq -
infinite: 1 ponder: 0 time: 0 increment: 0 moves to go: 0
 1   +1.82   00:00    1493  Qd1 Nxh3+ Kg2 Rxd8 
 2   +1.70   00:00    2037  Qe3 Nxh3+ Kh2 Rxd8 
 3   +1.70   00:00    2177  Qe3 Nxh3+ Kh2 Rxd8 
 4   +2.14   00:00    2554  Qe3 Nxh3+ Kh2 Rxd8 Nd2 
 5   +1.82   00:00    3340  Qe3 Nxh3+ Kh2 Rxd8 Nd2 Nf4 
 6   +2.30   00:00    6050  Qc2 Nxh3+ Kh1 Rxd8 d5 Ne7 Nd2 
 7   +1.82   00:00   13426  Qc2 Nxd8 dxe5 dxe5 c4 gxh3 cxb5 axb5 Qxc7 Rg8+ Kh2 
 8   +1.49   00:00   53599  Qc2 Nxd8 Nf5 gxh3 Nd2 h2+ Kh1 Be2 Rfe1 Nc6 
 9   +1.54   00:00   70210  Qc2 Nxd8 Nd2 gxh3 f3 Ne6 Nf5 Rg8+ Kh1 Rg2 d5 
10   +1.58   00:00  131180  Qc2 Nxd8 Nd2 gxh3 f3 Ne6 Kh1 exd4 cxd4 Nxd4 Qxc7 
11   +1.70   00:00  537582  Qe3 Rxd8 d5 Bh6 Qe1 Nxh3+ Kh2 Bg5 f3 Ne7 Nd2 Nf4 
                            Rb1 
12   +1.70   00:00  573716  Qe3 Rxd8 d5 Bh6 Qe1 Nxh3+ Kh2 Bg5 f3 Ne7 Nd2 Nf4 
                            Rb1 
13   +1.37   00:00   1000K  Qc2 Rxd8 d5 gxh3 f3 Rg8+ Kh1 Ne7 a4 Rg2 Nd2 c6 Rfe1 
                            Rf2 axb5 axb5 
14   +1.33   00:01   2055K  Qe1 Rxd8 d5 gxh3 f3 Ne7 Na3 Rg8+ Kh2 Bh6 Qf2 Bg5 
                            Rg1 Kd7 Rad1 Bxh4 Qxh4 Bxf3 
15   +1.33   00:01   2654K  Qe1 Rxd8 d5 gxh3 f3 Ne7 Na3 Rg8+ Kh2 Bh6 Qf2 Bg5 
                            Rg1 Kd7 Rad1 Bxh4 Qxh4 Bxf3 
16   +1.33   00:01   4414K  Qe1 Rxd8 d5 gxh3 f3 Ne7 Kh2 Bh6 Rg1 c6 dxc6 Nxc6 
                            Qf1 Ne7 Nd2 
17   +1.13   00:04  19967K  Qe1 Rxd8 d5 Ne7 Kh2 Bh6 Na3 gxh3 f3 Rg8 Rg1 Rxg1 
                            Qxg1 Kd7 Qa7 Bg5 Nf5 Nxf5 exf5 Nxd5 Qxa6 
18   +0.89   00:06  37425K  Qe1 Rxd8 Nf5 Nxh3+ Kg2 Nf4+ Kg3 Bg6 Rh1 Nd3 Qf1 
                            Rxh1 Qxh1 exd4 Qf1 Nc5 cxd4 Nxe4+ Kxg4 d5 Nc3 Bxf5+ 
                            Kxf5 Nxd4+ Kf4 
19   +1.17   00:13  82014K  Qd1 Rg8 f3 gxf3+ Kh2 Rxd8 Rf2 Be7 Nf5 Bf6 d5 Ne7 
                            Ng3 Bh4 Nxh5 Nxh5 Rxf3 Bg3+ Kg2 Bh4+ Kh1 Ng3+ Rxg3 
                            Bxg3 Nd2 Bf4 Nf3 
20   +0.93   00:22 146826K  Qe1 Rxd8 d5 Ne7 c4 gxh3 f3 Rg8+ Kh2 Bh6 Rg1 Kd7 
                            cxb5 Rxg1 Qxg1 Rg8 Qf1 Bg5 Nf5 Nxf5 exf5 Bf6 
21   +0.69   00:31 211975K  Qe1 Rxd8 Nd2 gxh3 Kh2 Be2 Nf5 Bxf1 Nxf1 Rg8 N1g3 
                            Ne7 Ne3 c5 Qd2 f6 a4 b4 Rd1 bxc3 bxc3 cxd4 cxd4 d5 
                            dxe5 fxe5 
22   +0.28   00:51 354312K  Qd1 g3 Qd2 Nxh3+ Kh1 Nxf2+ Kg2 Rxd8 Nf5 Bg6 Qe2 d5 
                            Nd2 Bxf5 exf5 e4 Kxg3 Bd6+ Kxf2 Rh2+ Ke3 Rxe2+ Kxe2 
                            Ke7 Ke3 Kf6 Rh1 Kxf5 Raf1+ Ke6 Rh6+ Ke7 Rh1 
23   +0.20   00:57 394323K  Qd1 g3 Qd2 Nxh3+ Kh1 Nxf2+ Kg2 Rxd8 Nf5 Bg6 Qe2 d5 
                            Nd2 Bxf5 exf5 e4 Kxg3 Bd6+ Kxf2 Rh2+ Ke3 Rxe2+ Kxe2 
                            Ke7 Rh1 Rg8 Rag1 Rxg1 Rxg1 Kf6 Rf1 Kg5 
24   +0.00   01:33 664668K  Qd1 g3 Qc2 g2 Re1 Rxd8 d5 Nxh3+ Kxg2 Nf4+ Kg1 Rg8+ 
                            Kf1 Bg4 Re3 Rh8 dxc6 Rxh4 Kg1 Ne2+ Kg2 Nf4+ Kg1 
25   +0.00   01:43 744094K  Qd1 g3 Qc2 g2 Re1 Rxd8 d5 Nxh3+ Kxg2 Nf4+ Kg1 Rg8+ 
                            Kf1 Bg4 Re3 Rh8 dxc6 Rxh4 Kg1 Ne2+ Kg2 Nf4+ Kg1 
26   +0.00   01:59 863415K  Qd1 g3 Qc2 g2 Re1 Rxd8 d5 Nxh3+ Kxg2 Nf4+ Kg1 Rg8+ 
                            Kf1 Bg4 Re3 Rh8 dxc6 Rxh4 Kg1 Ne2+ Kg2 Nf4+ Kg3 Be7 
                            f3 Be6 Qd2 Rh3+ Kf2 Rh2+ 
27   +0.00   02:29   1089M  Qd1 g3 Qc2 g2 Re1 Rxd8 d5 Nxh3+ Kxg2 Nf4+ Kg1 Rg8+ 
                            Kf1 Bg4 Re3 Rh8 dxc6 Rxh4 Kg1 Ne2+ Kg2 Nf4+ Kg3 Be7 
                            f3 
28   +0.00   03:13   1427M  Qd1 g3 Qc2 g2 Re1 Rxd8 d5 Nxh3+ Kxg2 Nf4+ Kg1 Rg8+ 
                            Kf1 Bg4 Re3 Rh8 dxc6 Rxh4 Kg1 Ne2+ Kg2 Nf4+ 
29   +0.00   04:50   2185M  Qd1 g3 Qc2 g2 Re1 Rxd8 Re3 exd4 cxd4 Nxd4 Qxc7 Bg4 
                            Nc3 Rxh4 Nd5 Nde2+ Rxe2 Nxe2+ Kxg2 Bxh3+ Kf3 Bg4+ 
                            Kg2 Bh3+ 
30   +0.00   07:42   3562M  Qd1 g3 Qc2 g2 Re1 Rxd8 Re3 exd4 cxd4 Nxd4 Qxc7 Bg4 
                            Nc3 Rxh4 Nd5 Nde2+ Rxe2 Nxe2+ Kxg2 Bxh3+ Kf3 Bg4+ 
                            Kg2 Bh3+ 
31   +0.00   11:46   5523M  Qd1 g3 Qc2 g2 Re1 Rxd8 Re3 exd4 cxd4 Nxd4 Qxc7 Bg4 
                            Nc3 Rxh4 Nd5 Nde2+ Rxe2 Nxe2+ Kxg2 Bxh3+ Kf3 Bg4+ 
                            Kg2 Bh3+ 
32   +0.00   27:08  13027M  Qd1 g3 Qb3 Nxh3+ Kh1 g2+ Kxg2 Nf4+ Kg1 Ne2+ Kg2 
                            Nf4+ 
33   +0.00   37:48  18241M  Qd1 g3 Qb3 Nxh3+ Kh1 g2+ Kxg2 Nf4+ Kg1 Ne2+ Kg2 

[Graham Banks]

However the horizon effect is quite apparent with this position

It was only recently that Alexander Schmidt was trying to convince me that today's top engines no longer suffered from the horizon effect.

[Dr.Wael Deeb]

However the horizon effect is quite apparent with this position

It was only recently that Alexander Schmidt was trying to convince me that today's top engines no longer suffered from the horizon effect.

The horizon effect does exist even at the highest levels among the chess engines....
Dr.D

[Graham Banks]

However the horizon effect is quite apparent with this position

It was only recently that Alexander Schmidt was trying to convince me that today's top engines no longer suffered from the horizon effect.

The horizon effect does exist even at the highest levels among the chess engines....
Dr.D

Agreed. For those interested, here is the thread in question:
http://talkchess.com/forum/viewtopic.ph ... zon+effect

Cheers,
Graham.

[Jack Lad]

16.Qe3? seems to lose after 17. ... Rxd8!
[d] r2Bkb1r/2p2p2/p1np4/1p2p2b/3PP1pN/2P1Q2n/PP3P2/RN3RK1 w kq - 0 17
16.Qe3 Nxh3+ 17.Kg2

(17.Kh2 Rxd8 18.Nd2 Bh6 19.Qe1 Nf4 20.Kg3 exd4 21.Nf5 Nd3 22.Qb1 Bf4+ 23.Kg2 dxc3 24.Qxd3 cxd2 25.Rh1 Kd7 26.Qe2 Ne5 27.a4 Rb8 28.axb5 axb5 29.Ng3 Bg6 30.Rxh8 Rxh8 31.Qxb5+ Ke7 32.Qb7 Nf3 33.Nf1 Kf6 34.Qb4 Ke5 35.Qb5+ c5 36.Qd7 Ng5 37.Ng3 Bxg3 38.Qe7+ Ne6 39.Kxg3 Bxe4 40.f4+ gxf3 41.Rd1 Rg8+ 42.Kh4 Rg2 43.b4 f2 44.Qxf7 Bf5 45.Qh5 Rh2+ 46.Kg3 Rxh5 47.Kxf2 Rh2+ 48.Ke3 d5 49.Kf3 Nf4 50.Rg1 Rg2 51.Rxg2 d1=Q+ 52.Ke3 Nh3 53.Rd2 d4+ 54.Rxd4 cxd4#)

17. ... Rxd8 18.Rh1 Bh6 19.Qe1 exd4 20.Nf5 Nf4+ 21.Kg3 d3 22.Nxh6 Ne2+ 23.Kg2 Nf4+ 24.Kf1 Rxh6 25.Qe3 Rf6 26.Nd2 Kd7 27.a4 Rg8 28.axb5 Ne5 29.Rxa6 g3 30.Rg1 Ne2 31.Rg2 Ng4 32.Qa7 gxf2 33.Rxd6+ Rxd6 34.e5 Re6 35.Qc5 Rg5 36.b6 cxb6 37.Qd5+ Ke7 38.Nc4 Nf4 39.Qa8 Rgxe5 40.Rxg4 Re1+ 41.Kxf2 R6e2+ 42.Kf3 Rf1+ 43.Kg3 Rg1+ 44.Kf3 Rxg4 45.Ne5 Rxe5 46.Qb7+ Kf6 47.Qd7 Kg5 48.Qd8+ f6 49.Qg8+ Kh4 50.Qxg4+ Bxg4+ 51.Kxf4 d2 52.c4 d1=Q 53.b3 Qd2#

[zullil]

Now at depth 36:

Code: Select all

36   +0.00 3:30:26 103858M  Qc2 Rxd8 Nf5 Nxh3+ Kg2 Nf4+ Kg1 Nh3+

[zullil]

Depth 39:

Code: Select all

39   +0.00 10:56:23 326307M  Qc2 Rxd8 Nf5 Nxh3+ Kg2 Nf4+ Kg1 Nh3+