20...Nc4! variation in van Foreest vs L'Ami (Dutch Ch. 2017)

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Vinvin
Posts: 4429
Joined: Thu Mar 09, 2006 8:40 am
Full name: Vincent Lejeune

20...Nc4! variation in van Foreest vs L'Ami (Dutch Ch. 2017)

Post by Vinvin » Sun Jul 09, 2017 1:24 pm

In the following position, Nc4!! is winning and hard to find by computers.
[d]1r2kb1r/p5p1/1np1p1N1/3pPnB1/1p1P2B1/qP6/2PQ1P1P/1K1R3R b k - 0 20

Video and posts about this sacrifice : https://lichess.org/forum/game-analysis ... win?page=1

Main variations in pgn :

[Event "Variation 20...Nc4!"]
[Site "-"]
[Date "2017.06.28"]
[White "Jorden van Foreest"]
[Black "Erwin L'Ami"]
[Result "1-0"]

1. e4 c6 2. d4 d5 3. e5 Bf5 4. Nc3 e6 5. g4 Bg6 6. Nge2 Be7 7. Be3 Nd7 8.
Qd2 h5 9. Nf4 hxg4 10. Nxg6 fxg6 11. O-O-O Nh6 12. Be2 Nf5 13. Bxg4 Qa5 14.
a3 b5 15. Bg5 Bf8 16. Ne2 b4 17. Nf4 Nb6 18. b3 Qxa3+ 19. Kb1 Rb8 20. Nxg6
Nc4 (20. .. Rh7 21. Bxf5 exf5 22. e6 Na4 23. bxa4 b3 24. c3 b2 25. h4 Bd6
26. Kc2 Qxa4+ 27. Kd3 Qc4+ 28. Ke3 Rb3 29. Kf3 Rxc3+ 30. Kg2 Qb3 31. Rb1
Rc2 32. Rh3 Qc4 33. Qa5 Be7 34. Nxe7 Rxf2+ 35. Kxf2 Qc2+ 36. Qd2) 21. bxc4
(21. Qc1 Qa5 22. Be2 (22. Nxf8) 22. .. Rb6 23. Bxc4 dxc4 24. Qb2) 21. .. b3
22. c3 b2 23. Bxf5 (23. Nxh8) 23. .. exf5 (23. .. Rxh2 24. Qe1 Qa1+ 25. Kc2
b1=Q+ 26. Rxb1 Qa2+ (26. .. Rxb1 27. Qxb1) 27. Kd3 Rxb1 28. Qxb1 dxc4+ 29.
Ke4 Qe2+ 30. Be3 exf5+ 31. Kxf5 Qh5+ 32. Ke6 Qg4+ 33. Qf5 Qxf5+ 34. Kxf5
Rxh1 35. d5 cxd5 36. Bxa7) 24. c5 (24. cxd5 Rh3 25. Be3 Qa1+ 26. Kc2 Qa4+
27. Kb1 (27. Kd3) 27. .. c5) 24. .. Rxh2 25. Rhf1 1-0

Original game :
[pgn]
[Event "Dutch Championships"]
[Site "Amsterdam NED"]
[Date "2017.06.28"]
[EventDate "2017.06.26"]
[Round "3.2"]
[Result "1-0"]
[White "Jorden van Foreest"]
[Black "Erwin L'Ami"]
[ECO "B12"]
[WhiteElo "2606"]
[BlackElo "2610"]
[PlyCount "71"]

1. e4 c6 2. d4 d5 3. e5 Bf5 4. Nc3 e6 5. g4 Bg6 6. Nge2 Be7
7. Be3 Nd7 8. Qd2 h5 9. Nf4 hxg4 10. Nxg6 fxg6 11. O-O-O Nh6
12. Be2 Nf5 13. Bxg4 Qa5 14. a3 b5 15. Bg5 Bf8 16. Ne2 b4
17. Nf4 Nb6 18. b3 Qxa3+ 19. Kb1 Rb8 20. Nxg6 Rh7 21. Bxf5
exf5 22. e6 Na4 23. bxa4 b3 24. c3 b2 25. h4 Bd6 26. Kc2 Qxa4+
27. Kd3 Qc4+ 28. Ke3 Rb3 29. Kf3 Rxc3+ 30. Kg2 Qb3 31. Rb1 Rc2
32. Rh3 Qc4 33. Qa5 Be7 34. Nxe7 Rxf2+ 35. Kxf2 Qc2+ 36. Qd2
1-0
[/pgn]

Vinvin
Posts: 4429
Joined: Thu Mar 09, 2006 8:40 am
Full name: Vincent Lejeune

Re: 20...Nc4! variation in van Foreest vs L'Ami (Dutch Ch. 2

Post by Vinvin » Sun Jul 09, 2017 1:25 pm

On one lucky run, SF (on a 6*4 GHz CPU) found Nc4 after 7m15s (4.5 billions nodes) :

Code: Select all

FEN: 1r2kb1r/p5p1/1np1p1N1/3pPnB1/1p1P2B1/qP6/2PQ1P1P/1K1R3R b k - 0 20
Stockfish_170702_x64_modern:
...
 41/26	01:56	 1 255 604k	10 760k	 0,00	20. ... Na4 21.bxa4 b3 22.c3 b2 23.Nxh8 Qa1+ 24.Kc2 Qxa4+ 25.Kd3 Qc4+ 26.Kc2 Qa4+
 42/26-	07:15	 4 627 797k	10 636k	-0,07	20. ... Nc4
 42/47-	08:23	 5 342 991k	10 615k	-0,14	20. ... Nc4
 42/68-	18:54	 12 073 885k	10 638k	-1,27	20. ... Nc4

pilgrimdan
Posts: 402
Joined: Sat Jul 02, 2011 8:49 pm

Re: 20...Nc4! variation in van Foreest vs L'Ami (Dutch Ch. 2

Post by pilgrimdan » Sun Jul 09, 2017 4:03 pm

Vinvin wrote:On one lucky run, SF (on a 6*4 GHz CPU) found Nc4 after 7m15s (4.5 billions nodes) :

Code: Select all

FEN: 1r2kb1r/p5p1/1np1p1N1/3pPnB1/1p1P2B1/qP6/2PQ1P1P/1K1R3R b k - 0 20
Stockfish_170702_x64_modern:
...
 41/26	01:56	 1 255 604k	10 760k	 0,00	20. ... Na4 21.bxa4 b3 22.c3 b2 23.Nxh8 Qa1+ 24.Kc2 Qxa4+ 25.Kd3 Qc4+ 26.Kc2 Qa4+
 42/26-	07:15	 4 627 797k	10 636k	-0,07	20. ... Nc4
 42/47-	08:23	 5 342 991k	10 615k	-0,14	20. ... Nc4
 42/68-	18:54	 12 073 885k	10 638k	-1,27	20. ... Nc4
after forcing Nc4... CM9_Botvinnik does not see the win for Black...

[d]1r2kb1r/p5p1/2p1p1N1/3pPnB1/1pnP2B1/qP6/2PQ1P1P/1K1R3R w k - 0 1
20:29 1/15 1.12 532982420 2.Qc1 Qa6 3.Bxf5 exf5 4.Rd3 Rg8
5.Nxf8 Na3+ 6.Kb2 Rxf8 7.Qf4 Nb5
8.Ra1 Qb7 9.e6 Nc3 10.e7 Rf7 11.Re1

Vinvin
Posts: 4429
Joined: Thu Mar 09, 2006 8:40 am
Full name: Vincent Lejeune

Re: 20...Nc4! variation in van Foreest vs L'Ami (Dutch Ch. 2

Post by Vinvin » Sun Jul 09, 2017 7:37 pm

pilgrimdan wrote:
Vinvin wrote:On one lucky run, SF (on a 6*4 GHz CPU) found Nc4 after 7m15s (4.5 billions nodes) :

Code: Select all

FEN: 1r2kb1r/p5p1/1np1p1N1/3pPnB1/1p1P2B1/qP6/2PQ1P1P/1K1R3R b k - 0 20
Stockfish_170702_x64_modern:
...
 41/26	01:56	 1 255 604k	10 760k	 0,00	20. ... Na4 21.bxa4 b3 22.c3 b2 23.Nxh8 Qa1+ 24.Kc2 Qxa4+ 25.Kd3 Qc4+ 26.Kc2 Qa4+
 42/26-	07:15	 4 627 797k	10 636k	-0,07	20. ... Nc4
 42/47-	08:23	 5 342 991k	10 615k	-0,14	20. ... Nc4
 42/68-	18:54	 12 073 885k	10 638k	-1,27	20. ... Nc4
after forcing Nc4... CM9_Botvinnik does not see the win for Black...

[d]1r2kb1r/p5p1/2p1p1N1/3pPnB1/1pnP2B1/qP6/2PQ1P1P/1K1R3R w k - 0 1
20:29 1/15 1.12 532982420 2.Qc1 Qa6 3.Bxf5 exf5 4.Rd3 Rg8
5.Nxf8 Na3+ 6.Kb2 Rxf8 7.Qf4 Nb5
8.Ra1 Qb7 9.e6 Nc3 10.e7 Rf7 11.Re1
Poor old CM9. 2...Qa6 is already a blunder. 2...Qa5 allows Rb6-Ra6 to threat mate.

Lyudmil Tsvetkov
Posts: 6052
Joined: Tue Jun 12, 2012 10:41 am

Re: 20...Nc4! variation in van Foreest vs L'Ami (Dutch Ch. 2

Post by Lyudmil Tsvetkov » Sun Jul 09, 2017 9:00 pm

Vinvin wrote:In the following position, Nc4!! is winning and hard to find by computers.
[d]1r2kb1r/p5p1/1np1p1N1/3pPnB1/1p1P2B1/qP6/2PQ1P1P/1K1R3R b k - 0 20

Video and posts about this sacrifice : https://lichess.org/forum/game-analysis ... win?page=1

Main variations in pgn :

[Event "Variation 20...Nc4!"]
[Site "-"]
[Date "2017.06.28"]
[White "Jorden van Foreest"]
[Black "Erwin L'Ami"]
[Result "1-0"]

1. e4 c6 2. d4 d5 3. e5 Bf5 4. Nc3 e6 5. g4 Bg6 6. Nge2 Be7 7. Be3 Nd7 8.
Qd2 h5 9. Nf4 hxg4 10. Nxg6 fxg6 11. O-O-O Nh6 12. Be2 Nf5 13. Bxg4 Qa5 14.
a3 b5 15. Bg5 Bf8 16. Ne2 b4 17. Nf4 Nb6 18. b3 Qxa3+ 19. Kb1 Rb8 20. Nxg6
Nc4 (20. .. Rh7 21. Bxf5 exf5 22. e6 Na4 23. bxa4 b3 24. c3 b2 25. h4 Bd6
26. Kc2 Qxa4+ 27. Kd3 Qc4+ 28. Ke3 Rb3 29. Kf3 Rxc3+ 30. Kg2 Qb3 31. Rb1
Rc2 32. Rh3 Qc4 33. Qa5 Be7 34. Nxe7 Rxf2+ 35. Kxf2 Qc2+ 36. Qd2) 21. bxc4
(21. Qc1 Qa5 22. Be2 (22. Nxf8) 22. .. Rb6 23. Bxc4 dxc4 24. Qb2) 21. .. b3
22. c3 b2 23. Bxf5 (23. Nxh8) 23. .. exf5 (23. .. Rxh2 24. Qe1 Qa1+ 25. Kc2
b1=Q+ 26. Rxb1 Qa2+ (26. .. Rxb1 27. Qxb1) 27. Kd3 Rxb1 28. Qxb1 dxc4+ 29.
Ke4 Qe2+ 30. Be3 exf5+ 31. Kxf5 Qh5+ 32. Ke6 Qg4+ 33. Qf5 Qxf5+ 34. Kxf5
Rxh1 35. d5 cxd5 36. Bxa7) 24. c5 (24. cxd5 Rh3 25. Be3 Qa1+ 26. Kc2 Qa4+
27. Kb1 (27. Kd3) 27. .. c5) 24. .. Rxh2 25. Rhf1 1-0

Original game :
[pgn]
[Event "Dutch Championships"]
[Site "Amsterdam NED"]
[Date "2017.06.28"]
[EventDate "2017.06.26"]
[Round "3.2"]
[Result "1-0"]
[White "Jorden van Foreest"]
[Black "Erwin L'Ami"]
[ECO "B12"]
[WhiteElo "2606"]
[BlackElo "2610"]
[PlyCount "71"]

1. e4 c6 2. d4 d5 3. e5 Bf5 4. Nc3 e6 5. g4 Bg6 6. Nge2 Be7
7. Be3 Nd7 8. Qd2 h5 9. Nf4 hxg4 10. Nxg6 fxg6 11. O-O-O Nh6
12. Be2 Nf5 13. Bxg4 Qa5 14. a3 b5 15. Bg5 Bf8 16. Ne2 b4
17. Nf4 Nb6 18. b3 Qxa3+ 19. Kb1 Rb8 20. Nxg6 Rh7 21. Bxf5
exf5 22. e6 Na4 23. bxa4 b3 24. c3 b2 25. h4 Bd6 26. Kc2 Qxa4+
27. Kd3 Qc4+ 28. Ke3 Rb3 29. Kf3 Rxc3+ 30. Kg2 Qb3 31. Rb1 Rc2
32. Rh3 Qc4 33. Qa5 Be7 34. Nxe7 Rxf2+ 35. Kxf2 Qc2+ 36. Qd2
1-0
[/pgn]
do they have at least a single analysis right at that lichess?

what about Nc4 Qc1 Qa5 Bd8

[d]1r1Bkb1r/p5p1/2p1p1N1/q2pPn2/1pnP2B1/1P6/2P2P1P/1KQR3R b k - 0 3

I don't see any quick mate, black might be winning very late into the endgame, but I doubt that too.

most likely a draw.

Lyudmil Tsvetkov
Posts: 6052
Joined: Tue Jun 12, 2012 10:41 am

Re: 20...Nc4! variation in van Foreest vs L'Ami (Dutch Ch. 2

Post by Lyudmil Tsvetkov » Sun Jul 09, 2017 9:34 pm

sorry, feeling a bit sleepy; I see black can capture with the king.

otherwise, that would be a nice deflection, possibly leading to a draw.

pilgrimdan
Posts: 402
Joined: Sat Jul 02, 2011 8:49 pm

Re: 20...Nc4! variation in van Foreest vs L'Ami (Dutch Ch. 2

Post by pilgrimdan » Sun Jul 09, 2017 10:15 pm

Vinvin wrote:
pilgrimdan wrote:
Vinvin wrote:On one lucky run, SF (on a 6*4 GHz CPU) found Nc4 after 7m15s (4.5 billions nodes) :

Code: Select all

FEN: 1r2kb1r/p5p1/1np1p1N1/3pPnB1/1p1P2B1/qP6/2PQ1P1P/1K1R3R b k - 0 20
Stockfish_170702_x64_modern:
...
 41/26	01:56	 1 255 604k	10 760k	 0,00	20. ... Na4 21.bxa4 b3 22.c3 b2 23.Nxh8 Qa1+ 24.Kc2 Qxa4+ 25.Kd3 Qc4+ 26.Kc2 Qa4+
 42/26-	07:15	 4 627 797k	10 636k	-0,07	20. ... Nc4
 42/47-	08:23	 5 342 991k	10 615k	-0,14	20. ... Nc4
 42/68-	18:54	 12 073 885k	10 638k	-1,27	20. ... Nc4
after forcing Nc4... CM9_Botvinnik does not see the win for Black...

[d]1r2kb1r/p5p1/2p1p1N1/3pPnB1/1pnP2B1/qP6/2PQ1P1P/1K1R3R w k - 0 1
20:29 1/15 1.12 532982420 2.Qc1 Qa6 3.Bxf5 exf5 4.Rd3 Rg8
5.Nxf8 Na3+ 6.Kb2 Rxf8 7.Qf4 Nb5
8.Ra1 Qb7 9.e6 Nc3 10.e7 Rf7 11.Re1
Poor old CM9. 2...Qa6 is already a blunder. 2...Qa5 allows Rb6-Ra6 to threat mate.
after ...Qa5 white's score does start to drop...

[d]1r2kb1r/p5p1/2p1p1N1/q2pPnB1/1pnP2B1/1P6/2P2P1P/1KQR3R w k - 0 2
Time Depth Score Positions Moves

2:24 1/12 1.60 62279924 3.Rd3 Na3+ 4.Kb2 Rg8 5.Bxf5 exf5
6.Qe3 Nb5 7.Ra1 Qb6 8.Qd2 c5 9.Nxf8
Kxf8 10.dxc5 Qxc5 11.Rxd5
8:08 1/13 1.05 207975989 3.Rd3 Rb6 4.bxc4 dxc4 5.Qb2 cxd3
6.Nxh8 dxc2+ 7.Qxc2 b3 8.Bh5+ Kd7
9.Qd2 Qxd2 10.Bxd2 Nxd4 11.Ba5 Rb5
23:51 1/14 0.98 604566725 3.Rd3 Rb6 4.bxc4 dxc4 5.Qb2 cxd3
6.Nxh8 dxc2+ 7.Qxc2 b3 8.Qb2 Ba3
9.Qa1 b2 10.Qa2 Nxd4 11.Bxe6 Qc3
12.Bf5

rabbits23
Posts: 144
Joined: Fri Sep 12, 2014 2:57 am
Location: Randwick Australia

Re: 20...Nc4! variation in van Foreest vs L'Ami (Dutch Ch. 2

Post by rabbits23 » Mon Jul 10, 2017 7:03 am

Thanks Vincent.I found Stephan's thorough explanation of this fascinating position very instructive and highly enjoyable.
rabbits :!:

whereagles
Posts: 561
Joined: Thu Nov 13, 2014 11:03 am

Re: 20...Nc4! variation in van Foreest vs L'Ami (Dutch Ch. 2

Post by whereagles » Mon Jul 10, 2017 8:20 am

It's not the first time that a top engine fails to see such a deep combination at lowish depths. They do eventually get there, but that is usually after time periods beyond LTC standards.

peter
Posts: 1816
Joined: Sat Feb 16, 2008 6:38 am
Full name: Peter Martan

Re: 20...Nc4! variation in van Foreest vs L'Ami (Dutch Ch. 2

Post by peter » Mon Jul 10, 2017 10:21 am

Hi Vincent!
Vinvin wrote:On one lucky run, SF (on a 6*4 GHz CPU) found Nc4 after 7m15s (4.5 billions nodes) :
Good found!

Most engines I tried get helped by higher contempt and by one next-best-move-command or 2MV.

Accordingly here is SF with Contempt 100 and 2MV, 24 threads Intel 12x2,67GHz- CPU:

Code: Select all

Engine: asmFishW_2017-07-04_popcntH (32768 MB)
von TypingALot

 21	 0:00 	+1.00 	20...Sa4 21.bxa4 b3 22.c3 b2 23.Lxf5 Txh2 24.De1 Txh1 25.Dxh1 exf5 26.Sxf8 Da1+ 27.Kc2 b1T 28.Txb1 Da2+ 29.Kd3 Txb1 30.Dh5+ Kxf8 31.Dh8+ Kf7 32.Dh5+ Kg8 33.De8+ Kh7 (23.765.023) 28632
 21	 0:00 	+2.89 	20...Txh2 21.Dd3 Txh1 22.Txh1 Sa4 23.Lc1 Sc3+ 24.Dxc3 bxc3 25.Lxa3 Lxa3 26.Lxf5 Kf7 27.Sh8+ Txh8 28.Txh8 exf5 29.Tc8 Le7 30.Txc6 g5 31.Txc3 g4 32.Kb2 f4 33.Tc6 (23.765.023) 28632
-----
 22	 0:05 	+1.00 	20...Sa4 21.bxa4 b3 22.c3 b2 23.Lxf5 Txh2 24.De1 Txh1 25.Dxh1 exf5 26.Sxf8 Da1+ 27.Kc2 b1T 28.Txb1 Da2+ 29.Kd3 Txb1 30.Dh5+ Kxf8 31.Dh8+ Kf7 32.Dh5+ Kg8 33.De8+ Kh7 (151.326.204) 27439
 22	 0:05 	+1.00 	20...Sc4 21.Dc1 Da5 22.Td3 Tb6 23.bxc4 dxc4 24.Lxf5 exf5 25.Ld8 Kxd8 26.Dg5+ Ke8 27.Dxf5 cxd3 28.Dc8+ Kf7 29.Sxh8+ Kg8 30.De6+ Kxh8 31.Dh3+ Kg8 32.De6+ Kh7 33.Dh3+ Kg8 (151.326.204) 27439
-----
 23	 0:05 	+1.00 	20...Sa4 21.bxa4 b3 22.c3 b2 23.Lxf5 Txh2 24.De1 Txh1 25.Dxh1 exf5 26.Sxf8 Da1+ 27.Kc2 b1T 28.Txb1 Da2+ 29.Kd3 Txb1 30.Dh5+ Kxf8 31.Dh8+ Kf7 32.Dh5+ Kg8 33.De8+ Kh7 (152.699.444) 27429
 22	 0:05 	+1.00 	20...Sc4 21.Dc1 Da5 22.Td3 Tb6 23.bxc4 dxc4 24.Lxf5 exf5 25.Ld8 Kxd8 26.Dg5+ Ke8 27.Dxf5 cxd3 28.Dc8+ Kf7 29.Sxh8+ Kg8 30.De6+ Kxh8 31.Dh3+ Kg8 32.De6+ Kh7 33.Dh3+ Kg8 (152.699.444) 27429
-----
-----
 26	 0:06 	+1.00 	20...Sa4 21.bxa4 b3 22.c3 b2 23.Lxf5 Txh2 24.De1 Txh1 25.Dxh1 exf5 26.Sxf8 Da1+ 27.Kc2 b1T 28.Txb1 Da2+ 29.Kd3 Txb1 30.Dh5+ Kxf8 31.Dh8+ Kf7 32.Dh5+ Kg8 33.De8+ Kh7 (167.902.046) 27408
 25	 0:06 	+1.00 	20...Sc4 21.Dc1 Da5 22.Td3 Tb6 23.bxc4 dxc4 24.Lxf5 exf5 25.Ld8 Kxd8 26.Dg5+ Kc7 27.Sxf8 cxd3 28.Dxg7+ Kc8 29.Dxh8 dxc2+ 30.Kxc2 Da2+ 31.Kd3 Db3+ 32.Ke2 Dc2+ 33.Kf1 Dc1+ (167.902.046) 27408
-----
 26	 0:13 	+0.22 	20...Sc4 21.bxc4 b3 22.c3 b2 23.Lxf5 Txh2 24.Thf1 exf5 25.c5 Lxc5 26.dxc5 Th3 27.Le3 Da1+ 28.Kc2 b1T 29.Txb1 Da4+ 30.Kc1 Txb1+ 31.Kxb1 Db5+ 32.Db2 Dxf1+ 33.Kc2 De2+ (357.134.942) 27450
 26	 0:13 	+1.00--	20...Sa4 21.bxa4 b3 22.c3 b2 23.Lxf5 Txh2 24.De1 Txh1 25.Dxh1 exf5 26.Sxf8 Da1+ 27.Kc2 b1T 28.Txb1 Da2+ 29.Kd3 Txb1 30.Dh5+ Kxf8 31.Dh8+ Kf7 32.Dh5+ Kg8 33.De8+ Kh7 (357.134.942) 27450
-----
-----
 28	 0:36 	-1.64 	20...Sc4 21.Dc1 Da5 22.Le2 Tb6 23.Lxc4 dxc4 24.Db2 Th3 25.Le3 Kf7 26.Thg1 c3 27.Da2 Dxa2+ 28.Kxa2 Txh2 29.Kb1 Tb8 30.Tc1 a5 31.Tg4 Le7 32.Tcg1 Ta8 33.Sf4 g5 (989.248.407) 26792
 27	 0:36 	+1.00 	20...Sa4 21.bxa4 b3 22.c3 b2 23.Lxf5 Txh2 24.De1 Txh1 25.Dxh1 exf5 26.Sxf8 Da1+ 27.Kc2 b1T 28.Txb1 Da2+ 29.Kd3 Txb1 30.Dh5+ Kxf8 31.Dh8+ Kf7 32.Dh5+ Kg8 33.De8+ Kh7 (989.248.407) 26792
-----
-----
 29	 1:03 	-1.69 	20...Sc4 21.Dc1 Da5 22.Le2 Tb6 23.Lxc4 dxc4 24.Db2 Th3 25.Da2 Dxa2+ 26.Kxa2 cxb3+ 27.cxb3 Ta6+ 28.Kb2 Ta3 29.Le3 Sxe3 30.fxe3 Txe3 31.Tdf1 Taxb3+ 32.Ka2 Tf3 33.Txf3 Txf3 (1.703.921.012) 26687
 29	 1:03 	+1.00 	20...Sa4 21.bxa4 b3 22.c3 b2 23.Lxf5 Txh2 24.De1 Txh1 25.Dxh1 exf5 26.Sxf8 Da1+ 27.Kc2 b1T 28.Txb1 Da2+ 29.Kd3 Txb1 30.Dh5+ Kxf8 31.Dh8+ Kf7 32.Dh5+ Kg8 33.De8+ Kh7 (1.703.921.012) 26687
-----
-----
 35	 2:18 	-1.96 	20...Sc4 21.bxc4 b3 22.c3 b2 23.Lxf5 exf5 24.c5 Txh2 25.The1 Tb3 26.Kc2 Txf2 27.Dxf2 b1L+ 28.Txb1 Da2+ 29.Kd3 Dxf2 30.Le3 Da2 31.Txb3 Dxb3 32.Ld2 Dc4+ 33.Kc2 Lxc5 (3.755.544.843) 27030
 35	 2:18 	+1.00 	20...Sa4 21.bxa4 b3 22.c3 b2 23.Lxf5 Txh2 24.De1 Txh1 25.Dxh1 exf5 26.Sxf8 Da1+ 27.Kc2 b1T 28.Txb1 Da2+ 29.Kd3 Txb1 30.Dh5+ Kxf8 31.Dh8+ Kf7 32.Dh5+ Kg8 33.De8+ Kh7 (3.755.544.843) 27030
-----
-----
 36	 3:24 	-2.12 	20...Sc4 21.Dc1 Da5 22.Le2 Tb6 23.Lxc4 dxc4 24.Db2 Th3 25.Da2 Dxa2+ 26.Kxa2 cxb3+ 27.cxb3 Ta6+ 28.Kb2 Ta3 29.Le3 Sxe3 30.fxe3 Txe3 31.Tdf1 Taxb3+ 32.Ka2 Tf3 33.Sxf8 Kxf8 (5.528.553.850) 27093
 36	 3:24 	+1.00 	20...Sa4 21.bxa4 b3 22.c3 b2 23.Lxf5 Txh2 24.De1 Txh1 25.Dxh1 exf5 26.Sxf8 Da1+ 27.Kc2 b1T 28.Txb1 Da2+ 29.Kd3 Txb1 30.Dh5+ Kxf8 31.Dh8+ Kf7 32.Dh5+ Kg8 33.De8+ Kh7 (5.528.553.850) 27093
20...Nc4 is second of two primary lines just after switching to 2MV (5sec.) and the leading one after 13sec
Peter.

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