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Very Hot Topic (More than 25 Replies) C42-C43: 1.e4 e5 2.Nf3 Nf6! :) (Read 32017 times)
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Re: C42-C43: 1.e4 e5 2.Nf3 Nf6! :)
Reply #41 - 06/12/15 at 23:08:09
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After this game I waited for further games but till now I only found this earlier game:



Was there something in CC?
  

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Re: 1.e4 e5 2.Nf3 Nf6! :)
Reply #40 - 06/03/10 at 04:18:48
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I have been trying to find this thread to resurrect for awhile now, especially after noticing that Bologan faced this 9...Bxa2 (7.Be3) line twice in a Blitz match in 2008, drawing both despite a rating advantage of more than 400 elo points.

A closer inspection of these games vindicates and confirms most of Nietzsche's analysis and evaluations posted almost 2yrs prior. Well done Nietzsche.

Has anyone made any further interesting discoveries in this line since the two games mentioned above.

Tops Smiley 
  

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Re: 1.e4 e5 2.Nf3 Nf6! :)
Reply #39 - 11/06/08 at 00:27:23
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This is something I can agree with wholeheartedly.
  

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Re: 1.e4 e5 2.Nf3 Nf6! :)
Reply #38 - 11/06/08 at 00:20:06
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Typos really are pretty unavoidable! Cheesy

And you seem to be saying that you think the exchange sac is playable at least.  I don't see any refutation of ...Bxa2.
So, this line would be my personal choice if I were White.
Like I said, I think it would be rather tough to face this Rb1 (and exchange sacrifice) over-the-board.  Especially since there is nothing out there on it!

Anyway, I think this ...Bxa2 move was over-estimated by some Black players because of the van Delft game or because their opponent's didn't know what hit them.  With proper play, I would still prefer to be white.  That said, Black may indeed have a practical edge if he knows what's going on and White doesn't.

Black gets a tactical, complicated position via ...Bxa2, and while I cannot find an edge for him, I might play it if I absolutely NEEDED to win the game. But ultimately, I still don't think its superior to the existing theory (for black).

Let's face it, while the white setup (after 5.Nc3) is rather simple, it is not at all easy for black to play for the win.  I think this setup is a rather decent way to play for white players both:
(A) happy with a draw
(B) wanting to avoid the mainlines with 5.d4.  


So, I guess both sides really need be aware of this ...Bxa2 idea, since these lines are not very intuitive or simple to spot.  I'm glad I studied it even though I no longer play the Petroff.

Nietzsche
  

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Re: 1.e4 e5 2.Nf3 Nf6! :)
Reply #37 - 11/05/08 at 23:54:45
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I think 19...Ra2+ (you're right) 20.Kc1 (fortunately I am not the only one who's plagued by typos  Tongue) Ra1 21.Qe1 Rxb1+ 22.Kxb1 Qa3 unclear enough to call "better for White" premature.
  

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Re: 1.e4 e5 2.Nf3 Nf6! :)
Reply #36 - 11/05/08 at 22:38:15
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RE: "Nothing at the moment, because I find it hard to evaluate 19...Ra1 iso 19...Qa5. "

Do you mean 19..Ra2?   Huh
(which is better for white after 20.Kb1 Ra1 21.Qe1)

because 19...Ra1 just hangs the rook.
  

"By some ardent enthusiasts Chess has been elevated into a science or an art. It is neither; but its principal characteristic seems to be what human nature mostly delights in - a fight." - Em. Lasker
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Re: 1.e4 e5 2.Nf3 Nf6! :)
Reply #35 - 11/05/08 at 10:10:58
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Nietzsche wrote on 11/04/08 at 05:03:56:
RE: "16...d5 is an obvious improvement here, that probably wins a tempo: 17.Kc1 (anything better here?)

Well...maybe!?
First of all, I think you're right about 16...d5 as an improvement.

But since white wants to ease the QS pressure, what about an exchange sacrifice?  Grin
I think this is rather interesting for white since he can get the bishop pair, a safer king, and probably another pawn.

17.Ra1 and black is almost forced into 17 ... Ba3+.  and now my idea is:
18. Rxa3!? Rxa3
19. Rb1!  Qa5!? (best?)
20. Kc1  ...

And I think White has good compensation here.  His king is now safe and I like the chances of those bishops coming to life.  
Also, I think black players could easily go wrong OTB with something  like 20...Rxc3 21.Bxc7! or even the horrible 20...Qxc3?? when I think he's just lost!

But even with best play after 20. Kc1 (which might be 20 ... Ra1  21. Qe1!), I'd prefer to be white.

So, what do you think of this exchange sacrifice? Huh

Nietzsche


Nothing at the moment, because I find it hard to evaluate 19...Ra1 iso 19...Qa5.
  

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Re: 1.e4 e5 2.Nf3 Nf6! :)
Reply #34 - 11/04/08 at 05:26:41
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RE:  "The difference is 0-0 16.Bd3 (16.Be2 d5 17.Kc1 Ra1) d5 17.Kc1 Ra1 18.Qe1 Rxb1+ 19.Kxb1 and Black does not have the tempo-win Qa4."


Interesting...I didn't look at that.  
As black, I think I'd play 18...Bf6!? and try to avoid swapping rooks (to keep up the pressure).
Even still, I think white comfortably stays a little bit better in the line with 7.Be3.
So, I'd prefer to "hang" my bishop against the 7.Bf4 setup.

Nietzsche

p.s. - I mentioned the idea was "antithetical' only because I tend to try and find moves that are in the spirit of the opening.  
In general, I've found such moves tend to be better in the long haul --- I don't know why exactly--- but it's been my experience.  Clearly, that's not meant to be a big, knock-down argument or something; just a personal preference. Wink
  

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Re: 1.e4 e5 2.Nf3 Nf6! :)
Reply #33 - 11/04/08 at 05:03:56
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RE: "16...d5 is an obvious improvement here, that probably wins a tempo: 17.Kc1 (anything better here?)

Well...maybe!?
First of all, I think you're right about 16...d6 as an improvement.

But since white wants to ease the QS pressure, what about an exchange sacrifice?  Grin
I think this is rather interesting for white since he can get the bishop pair, a safer king, and probably another pawn.

17.Ra1 and black is almost forced into 17 ... Ba3+.  and now my idea is:
18. Rxa3!? Rxa3
19. Rb1!  Qa5!? (best?)
20. Kc1  ...

And I think White has good compensation here.  His king is now safe and I like the chances of those bishops coming to life.  
Also, I think black players could easily go wrong OTB with something  like 20...Rxc3 21.Bxc7! or even the horrible 20...Qxc3?? when I think he's just lost!

But even with best play after 20. Kc1 (which might be 20 ... Ra1  21. Qe1!), I'd prefer to be white.

So, what do you think of this exchange sacrifice? Huh

Nietzsche
  

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Re: 1.e4 e5 2.Nf3 Nf6! :)
Reply #32 - 11/04/08 at 02:14:05
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Quote:
However...15. Rb1!? is a simple but interesting novelty that would be my personal choice.  It avoids trouble and still leaves white a touch better after something like 15...O-O 16. Bd3 Ra2+ 17. Kc1 Ra1 18. Qd1 Bf6 19. Rxa1 Qxa1+ 20. Kd2 Bxc3+ 21. Ke2 Re8+ 22.Be3 Qa5 23. Kf1.)

16...d5 is an obvious improvement here, that probably wins a tempo: 17.Kc1 (anything better here?) Ra1 18.Qd1 Rxa1+ 19.Kxb1 Qa5 and Black's attack is not over yet. After 18.Qe1 Rxb1+ 19.Kxb1 Qa4 play is rather unclear.

Quote:
But 15.Bc4!? d5! 16. Bxc7!
(16. Bb3 Ba3+ 17. Kb1 Be7 18. Kb2 Ba3+ would be cowardly)

16... O-O!
(Toppy is right) Perhaps, but what is wrong with 16...b5 17.Bxd5 Rb5+ 18.Bb3 Qa3+ 19.Kb1 0-0 20.Qc1 Qa5 21.Qf4 g5 ?

17. Bxa5 Nxa5 18. Ne5 Ba3+ 19. Kb1 Nxc4 20. Nxc4 dxc4 21. Qd7 b5 22. Rd5?

and 22...Bb4 23.cxb4 c3 24.Rd3 Qa3 25.Rxc3 Qxc3 might be pretty strong as well.

Quote:
And so I recommend that white try the novelty:
---22.Rhe1!? ...
A simple developing and centralizing move that dares Black to take a pawn.

22. ... b4!? 23. Qd5! Qb8

Black might have 23...Qa6 and 24.Qd6 Qa6 25.Qd5 Qa6 repeats. White can avoid the draw with 25.cxb4 Bxb4 26.Qxb4 Rb8 27.c3 h6 but it will be a hard fight. A better try might be 24.Re5 bxc3 25.Qb5 though this transposes to your main line.

Quote:
not to mention its a bit antithetical to the Russian Defense.

A bit silly argument, so it's a good idea not to mention it. Overall excellent analysis, that will encourage fans of Black's play.

Quote:
(BTW: if 7. Be3 (I think white's extra control over d4 makes the ...Bxa2 idea less appealing.)
7. ...Nc6 8. Qd2 Be6 9. O-O-O Bxa2?! 10. b3 a5 11. Kb2 a4 12. Kxa2 axb3+ 13. Kxb3 Ra5 14. Kb2 Qa8 15. Rb1 and White stays on top).

The difference is 0-0 16.Bd3 (16.Be2 d5 17.Kc1 Ra1) d5 17.Kc1 Ra1 18.Qe1 Rxb1+ 19.Kxb1 and Black does not have the tempo-win Qa4.
  

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Re: 1.e4 e5 2.Nf3 Nf6! :)
Reply #31 - 11/03/08 at 01:34:35
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PART II:

It's time to get back to our 15. Bc4!?   - which I think is well met by:
15... d5!

16. Bxc7!

(16. Bb3 Ba3+ 17. Kb1 Be7 18. Kb2 Ba3+ would be cowardly)

16... O-O! (Toppy is right)

17. Bxa5 Nxa5
18. Ne5 ...

(18. Bxd5?? Nc4+ 19. Bxc4 Qa3+ 20.Kb1 Ra8 and sign it 0-1)

18... Ba3+
19. Kb1 Nxc4
20. Nxc4 dxc4
21. Qd7 b5
---22. Rd5? ...


this was the amateur game (Berbatov-Lambert 2008) but I think it is not best thanks to:
22. ... b4!
23. Qb5 bxc3   (23...Rb8 will probably just transpose)
24. Qa5 Rb8+
25. Ka2 Qb7!    now Black might just be winning after this shot...
26. Rb5 Qxb5
27. Qxb5 Rxb5
28. Kxa3 Rb2
 (and white is effectively a king down in this ending.)





And so I recommend that white try the novelty:
---22.Rhe1!? ...
A simple developing and centralizing move that dares Black to take a pawn.

22. ... b4!? probably the best.

(Black should probably avoid 22...Qxg2?!  since 23. Qa7! b4  white can double the rooks and his play continues, while the black bishop is out of play (and the black queenside action is frozen).  Alternatively, White can rush his kingside pawns up to try and denude the Black king and go for the throat.  
Either way, White has all the play here, with active pieces and multiple ways to play for the win.  I would hate this position as Black.

23. Qd5! Qb8
24. Re5 bxc3+
25. Qb5 Qa8
26. Qa5! ...


(26. Qxc4 Bb2 27. Qa2 Qxg2 is unclear, but I think allows black too much play)

And now Black might try something like:
26.  ... Qb8+?
27. Rb5 Qe8
28. Rb7 Qe2
29. Rd8 ...
but now white is really much better.

So, I prefer:
26. ... Rb8+
27. Ka2 Bf8!
 ("A man's got to know his limitations" - GM Dirty Harry)
28. Qxa8  Rxa8+
29. Kb1  Rb8+    
30. Ka1  Ra8+
31. Kb1  Rb8+

and shake hands.

Another, simpler,  try is:
---22. Qd5!? Qa5  (...Qa6!? might be better)
23. Rhe1 Ra8
24. Qc6 Bf8
25. Kc1 Ra6
26. Qc8 Ra8

With a probable repetition of moves.

Still I don't think ...Bxa2 is Black's best try in the original position; not to mention its a bit antithetical to the Russian Defense.
Wink

However, I am absolutely certain that 22.Rd5? is a mistake.
As White I'd prefer either 22.Rhe1 or 22.Qd5.
But, personally, I would avoid all this with either 14.Rb1 or 15.Rb1.  Perhaps deviate even earlier with 9.Bd3 and avoid the mess after ...Bxa2.

Anyway, I'm sure there's room to improve this analysis (it goes up to move 30 afterall), but I thought I'd share my findings today with other chess enthusiasts.  I really enjoyed analyzing the lines after 12.Ra1 since Black has many interesting attacking ideas.  Its good fun, but from a theoretical standpoint, I'm afraid it just doesn't matter.
Alas!

Cheers,
Nietzsche
« Last Edit: 11/03/08 at 21:39:08 by Nietzsche »  

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Re: 1.e4 e5 2.Nf3 Nf6! :)
Reply #30 - 11/03/08 at 00:58:50
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I took some time today to look into this ...Bxa2 idea for Black.
Unfortunately, I don't think it promises more than the normal and "safe" idea of ...Qd7, ...a6.
 In fact, a well-prepared White player really should come away with an edge.  Anyway...here is some analysis for those who care;  I'll post it in parts

Nietzsche

p.s. - please forgive any formatting mistakes.
======================================

1. e4 e5
2. Nf3 Nf6
3. Nxe5 d6
4. Nf3 Nxe4
5. Nc3 Nxc3
6. dxc3 Be7
7. Bf4 .
.
.

(BTW: if 7. Be3 (I think white's extra control over d4 makes the ...Bxa2 idea less appealing.)
7. ...Nc6
8. Qd2 Be6
9. O-O-O Bxa2 ?!
10. b3 a5
11. Kb2 a4
12. Kxa2 axb3+
13. Kxb3 Ra5
14. Kb2 Qa8
15. Rb1  ...   and white stays on top).

7. ... Nc6
8. Qd2 Be6
9. O-O-O Bxa2!?

(note: 9. Bd3!? safely avoids the issue if white so desires)


10. b3 a5
11. Kb2 a4
12. Kxa2!...
picking up the gauntlet is best.

For example, a fun line is:  
12. Ra1 axb3
13. cxb3 Bxb3
14. Rxa8 Qxa8
15. Kxb3 Qa1!  
16. Qc1 Na5+
17. Kc2...


of course not 17. Kb4?? d5+ 18. Kb5 Qa2!
White can now pick his poison:
(I)  19. Bxc7  Nc4! 20. Bxc4 Qa6#
(II) 19. Qd2 Qb3+ 20. Kxa5 Qa3+ 21. Kb5 Qa6#


17. ... Qa4+
18. Kd3 ...


(18. Kb2? Qb3+ 19. Ka1 Bf6! and black is better)
(18. Kb1 O-O! is rather unclear, though I prefer black)

18. ... O-O
19. Be3 d5!?  and black has c4 for the knight, e-file for the rook, a menacing queenside pawn brigade and that weak white monarch to harass as well.


(Note that White is even worse after 19. Be2? Qc4+ and 20. Kc2 Qxe2+  -or - 20. Ke3 Qe6+ 21. Kd3 Qf5+ 22. Ke3 Re8 23. Nd4 Bh4+ 24. Kd2 Qxf4+ 25. Kc2 Qxf2.)


12. ... axb3+
13. Kxb3 ...


(of course 13. Kb2? is bad due to 13...Ra2+ and now something like:
14. Kxb3 Qa8
15. Kc4 ...

(if 15. Bb5 Qa3+ 16. Kc4 Qc5+ and white loses with either:
--- 17. Kd3 Qxb5+ 18.Ke3 g5!
--- 17. Kb3 Ra3+ 18. Kb2 Qxb5+ 19. Kxa3 O-O  (and mate via ...Ra8)


15. ... Qa6+
16. Kd5 Qa4!
this clever move wins the game for black.

13... Ra5

(13... O-O? 14. Bd3 Bf6 15. Ra1 Na5+ 16. Kb2)

14. Kb2 ...
(14. Rb1!? Qa8 15. Kb2! d5 16. Kc1 looks good for white)

14. ... Qa8
15. Bc4!? ...


(15. Qe3 is playable, but after 15...O-O! 16. Rb1!? Bf6 (and ...d5 to come) I prefer Black.)

However...15. Rb1!? is a simple but interesting novelty that would be my personal choice.  It avoids trouble and still leaves white a touch better after something like 15...O-O 16. Bd3
Ra2+ 17. Kc1 Ra1 18. Qd1 Bf6 19. Rxa1 Qxa1+ 20. Kd2 Bxc3+ 21. Ke2 Re8+ 22.Be3 Qa5 23. Kf1
.)

But 15.Bc4!? is the critical try for this thread....see next post.
« Last Edit: 11/03/08 at 04:21:26 by Nietzsche »  

"By some ardent enthusiasts Chess has been elevated into a science or an art. It is neither; but its principal characteristic seems to be what human nature mostly delights in - a fight." - Em. Lasker
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Re: 1.e4 e5 2.Nf3 Nf6! :)
Reply #29 - 10/26/08 at 20:07:59
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chessbase had a article on the rybka opening software, has an interesting line on the petroff, involving an interesting piece sac.

http://www.chessbase.com/newsdetail.asp?newsid=4964

  
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Re: 1.e4 e5 2.Nf3 Nf6! :)
Reply #28 - 10/08/08 at 00:05:15
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TopNotch wrote on 10/07/08 at 22:36:25:
Kaziglub wrote on 10/04/08 at 19:37:57:
RandomPatzer wrote on 10/04/08 at 10:32:00:
16. Bxc7 b6 17.Bxd5 Ba3+ 18.Kb1 0-0 19.Qd3! intending 19...Bc5+ 20.Kc1 Ba3+ 21.Kd2
16. Bxc7 Rc5 17.Bxd5 0-0 18.Ra1
16. Bxc7 dxc4 17.Bxa5 Qxa5 18.Qd7+ Kf8 19.Qxb7
16. Bxc7 Ra7 17.Qxd5

all look completely winning for white to me. What am I missing?

something guy, come on !  Smiley


1.e4 e5 2.Nf3 Nf6 3.Nxe5 d6 4.Nf3 Nxe4 5.Nc3 Nxc3 6.dxc3 Be7 7.Bf4 Nc6 8.Qd2 Be6 9.0-0-0 Bxa2 10.b3 a5 11.Kb2 a4 12.Kxa2 axb3+ 13.Kxb3 Ra5 14.Kb2 Qa8 15.Bc4 d5 16.Bxc7 0-0! 17.Bxa5 Nxa5 18.Ne5 Ba3+ 19.Kb1 Nxc4 20.Nxc4 dxc4 21.Qd7 b5 22.Rd5 b4 23.Qb5 bxc3 24.Qa5 Rb8+ 25.Ka2 Qb7! 26.Rb5 (26.Kxa3 Qb2+ 27.Ka4 Qa2 Mate; 26.Qxa3 Qxd5 27.Qxc3 Qb7-+) 26...Qxb5 27.Qxb5 Rxb5 28.Kxa3 Rb2 29.Re1 f5 30.Re2 Kf7 And Black is clearly better.

That's what you are missing.

The ball would now appear to be in White's court, but as a supporter of the White side in this variation, I can confide that there is plenty room for improvement. Indeed I have a few such improvements handy, just waiting to be sprung on those foolhardy enough to enter this suicidal pawn grab line.

Sadly few players have the cojones to play this way in OTB chess.

Toppy
Smiley  


maybe one day  Smiley
  
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Re: 1.e4 e5 2.Nf3 Nf6! :)
Reply #27 - 10/08/08 at 00:00:03
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TopNotch wrote on 10/07/08 at 22:36:25:
Indeed I have a few such improvements handy, just waiting to be sprung on those foolhardy enough to enter this suicidal pawn grab line.

Sadly few players have the cojones to play this way in OTB chess.

Toppy[/b][/color] Smiley  


Try to find IM Van Delft. Will be interesting.
  

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