Page Index Toggle Pages: 1 2 3 [4] 5 6 ... 20
Topic Tools
Very Hot Topic (More than 25 Replies) Caro Advance: 4 Nc3 a6 (Read 22944 times)
HgMan
God Member
*****
Offline


Demand me nothing: What
you know, you know

Posts: 2330
Location: Up on Cripple Creek
Joined: 11/09/04
Gender: Male
Re: Caro Advance: 4 Nc3 a6
Reply #245 - 07/30/06 at 00:42:03
Post Tools
Let's not take 24 ... Rc4 off the table!   Grin
  

"Luck favours the prepared mind."  --Louis Pasteur
Back to top
 
IP Logged
 
OstapBender
God Member
*****
Offline


There is no spoon.

Posts: 1491
Location: not in Kansas anymore
Joined: 10/16/04
Re: Caro Advance: 4 Nc3 a6
Reply #244 - 07/30/06 at 00:40:32
Post Tools
HgMan wrote on 07/30/06 at 00:12:14:
This does look persuasive, but what about 25 b3 25 ... b4 26 Rxc8 Rxc8 27 Rc1 ?  I presume Black has 27 ... Rc6 28 f5 Ke7 29 Rc2, but I think the chances are White's again.

25.b3 is clearly an important idea, and one which I didn't consider.  I'll take a look at this and see if I'm still willing to recommend 24...Kd7.
  

"If God had wanted us to vote, he would have given us candidates."  -Jay Leno
Back to top
 
IP Logged
 
OstapBender
God Member
*****
Offline


There is no spoon.

Posts: 1491
Location: not in Kansas anymore
Joined: 10/16/04
Re: Caro Advance: 4 Nc3 a6
Reply #243 - 07/30/06 at 00:34:31
Post Tools
Smyslov_Fan wrote on 07/30/06 at 00:12:28:
Ostap,

I think there's a hole in your analysis big enough to drive ....err... to drive something large through it.

All White needs to do to win is trade off both Rooks to win the endgame, and it pretty much doesn't matter where.  (Ok, I haven't researched ...Rc6 yet.)

Here are some lines.  The Queen ending was with Fritz' help, the pawn endings were in spite of Fritz.  (My German friend kept telling me not to do it until I showed him.  That's what really good friends are for, to disagree with you until you show them they're wrong, then abjectly admit your superiority! Roll Eyes)

Here are the main pawn ending lines:




1...Kd7 2.Rxc8 Rxc8 3.Rc1 Rc4 

[3...Rxc1 4.Kxc1

...and so on.....

Yes SF, only a true friend would be so brutally honest! Wink

So, in the spirit of true friendship, I must comment:

I'm sure there's some great analysis here after 3.Rc1, although I haven't looked at any of it yet.  Unless you can tell me why Black needs to play 3...Rc4? or 3...Rxc1? I may be able to save a bit of time by not looking at any of it!

Why not simply play 3...Ra8 - what great plan am I too obtuse to pick up on here??  Please enlighten me!

Then I can feel justified in taking the time to drive my truck through this gaping hole you are trying to show me! Grin

(Looks like I missed you second post which occurred while I was writing this one.  White's response to 3...Ra8 is still a hanging question!)
  

"If God had wanted us to vote, he would have given us candidates."  -Jay Leno
Back to top
 
IP Logged
 
Smyslov_Fan
God Member
Correspondence fan
*****
Offline


Progress depends on the
unreasonable man. ~GBS

Posts: 6902
Joined: 06/15/05
Re: Caro Advance: 4 Nc3 a6
Reply #242 - 07/30/06 at 00:20:03
Post Tools
If my last post is right, then Black's best may be ...Ra8.  I don't hold much hope for that either, but it has to be better than the pawn endings.
  
Back to top
 
IP Logged
 
Smyslov_Fan
God Member
Correspondence fan
*****
Offline


Progress depends on the
unreasonable man. ~GBS

Posts: 6902
Joined: 06/15/05
Re: Caro Advance: 4 Nc3 a6
Reply #241 - 07/30/06 at 00:12:28
Post Tools
Ostap,

I think there's a hole in your analysis big enough to drive ....err... to drive something large through it.

All White needs to do to win is trade off both Rooks to win the endgame, and it pretty much doesn't matter where.  (Ok, I haven't researched ...Rc6 yet.)

Here are some lines.  The Queen ending was with Fritz' help, the pawn endings were in spite of Fritz.  (My German friend kept telling me not to do it until I showed him.  That's what really good friends are for, to disagree with you until you show them they're wrong, then abjectly admit your superiority! Roll Eyes)

Here are the main pawn ending lines:




1...Kd7 2.Rxc8 Rxc8 3.Rc1 Rc4 

[3...Rxc1 4.Kxc1 Kc6 5.Kc2 b4 6.Kb3 Kb5 7.f5 b6 8.f6 gxf6 9.exf6 Ka5 10.g5] 

4.Rxc4 bxc4 

[4...dxc4 5.Kc3 Kc6 6.a4 Kd5 7.a5 

(7.axb5 Ke4 8.Kxc4 Kxf4 9.Kc5 Kxg4 10.Kb6 Kxh5 11.Kxb7 g5 12.b6 g4 13.Kc6 g3 14.b7 g2 15.b8Q g1Q 16.Qf8 and even this Queen ending is winning eventually, but White has better.) 
7...Ke4 8.Kb4! Kxd4 9.Kxb5 Ke4 10.Kb6 Kxf4 11.Kxb7 and White wins] 
5.Kc3 Kc6 

[No, other moves don't change the result.  For instance, 5...Ke8 6.Kb4 g6 7.Kb5 gxh5 8.gxh5 Kd7 9.Kb6 Kc8 10.a4 Kb8 11.a5 Kc8 12.a6 bxa6 13.Kxa6 Kc7 14.Kb5 Kb7 15.Kc5 Kc7 16.f5! you guessed it.  White wins again.; 

5...Kc7 6.Kb4 Kb6 7.f5 exf5 8.gxf5 Kc6 9.Ka5 Kc7 10.Kb5] 6.Kb4 b5 7.Ka5 g6 8.g5 And again, White wins.


It's always amazing to me how thematic moves have a way of being... thematic.  White's f4-f5 push has been a threat since the opening and is one of the key deciding ideas in the endgame.  Going back to a certain Nimzo thread, it seems that "the threat is greater than the execution" yet again.

HgMan and Willempie,

How's my analysis?  Is this what you've been seeing?


Cheers!
  
Back to top
 
IP Logged
 
HgMan
God Member
*****
Offline


Demand me nothing: What
you know, you know

Posts: 2330
Location: Up on Cripple Creek
Joined: 11/09/04
Gender: Male
Re: Caro Advance: 4 Nc3 a6
Reply #240 - 07/30/06 at 00:12:14
Post Tools
This does look persuasive, but what about 25 b3 25 ... b4 26 Rxc8 Rxc8 27 Rc1 ?  I presume Black has 27 ... Rc6 28 f5 Ke7 29 Rc2, but I think the chances are White's again.

Having said that, there are parallels between your analysis and what I was looking at after 24 ... Rc4.  Instead of Rc4-a4 (which is typically impossible, because White has played b2-b3), Black can swing his other rook from h8 to a8 and exert similar kinds of pressure, while his king protects the kingside pawns.

But this is food for thought.  Thank you!  I'll be sure to give this some careful consideration while I further examine this endgame.  I am, however, feeling fairly confident that I can hold...
  

"Luck favours the prepared mind."  --Louis Pasteur
Back to top
 
IP Logged
 
OstapBender
God Member
*****
Offline


There is no spoon.

Posts: 1491
Location: not in Kansas anymore
Joined: 10/16/04
Re: Caro Advance: 4 Nc3 a6
Reply #239 - 07/29/06 at 23:20:47
Post Tools
Here is some analysis of 24...Kd7 which leads me to believe that Black has resources to defend against the kingside pawnstorm which should be sufficient to hold a draw (easily):

24...Kd7 25.Rxc8 Rxc8 26.f5 Rc4 Forcing the king to defend d4 and intending to swing over to the a-file to hit the a2-pawn.

27.Kd3 Ra4 28.Rf1

[I see no problems after 28.a3 b4 29.axb4 (29.fxe6+ Kxe6 30.axb4 Rxb4 is no improvement) 29...Rxb4 30.Kc3 Rc4+ 31.Kd3 but I guess this could be analyzed further to be sure.]

28...Rxa2 29.f6 gxf6 30.Rxf6 Now the h6-pawn will fall, but this is not as bad as it might seem.  Black defends pretty easily.

30...Ke7 31.Kc3 (probably best)

[31.Rxh6 Rxb2 32.Rh8 (32.g5 Rg2) 32...Rg2 33.Rg8 Rh2 34.Ke3 b4 35.Rb8 b3 36.Rxb7+ Kf8 37.Kf4 (since 37.Rxb3?? drops a rook after Rh3+) 37...b2 looks pretty safe for Black; for example, 38.Kg5 Kg7 and I don’t see a way for White to make progress.]

31...Ra8 32.Rxh6 Rg8 33.g5 Rxg5 34.Rh8

[34.Kb4 can be answered by 34…Rg4.  Then 35.Kc5 b6+ 36.Kxb6 Rxd4 37.Kxb5 Re4 and I think it is White who has to worry.]

34...f5

[34...Rg4 also looks reasonable: 35.Rb8 b4+ 36.Kxb4 Rxd4+ 37.Kc3 Rh4]

35.Rh7+

[35.h6 Rh5 36.h7 Kf7 and the h7-pawn will fall.]
[35.exf6+ Kxf6 36.h6 Rh5 is also no problem for Black.]

35...Ke8 36.h6

[36.Rxb7 Rxh5 37.Rxb5 doesn’t look threatening (similar to the main line)]

36...Rh5 37.Rxb7

[37.Kb4 f4 38.Rxb7 (If 38.Kxb5? then 38...f3 looks very dangerous) 38...Rxh6]

37...Rxh6 38.Rxb5 and Black should have no trouble drawing.

This is not comprehensive, but unless there is an obvious hole somewhere I think Black has no problems holding a draw.  

By comparison, I thought the 24...Rc4 lines looked a lot less clear and I wonder if White still might have serious winning chances in those lines.  Mainly, I see the c6-pawn as more of a liablity than a source of black counterplay (the doubled b-pawns may look weaker, but I not so sure that they actually are weaker when the white king and rook have other commitments).  Lines where White winds up with a passed a-pawn seem unacceptable if White is still able to pawn storm on the kingside.

Maybe I haven't looked at 24...Rc4 carefully enough (probably true), but I'd much rather go with 24...Kd7.
  

"If God had wanted us to vote, he would have given us candidates."  -Jay Leno
Back to top
 
IP Logged
 
HgMan
God Member
*****
Offline


Demand me nothing: What
you know, you know

Posts: 2330
Location: Up on Cripple Creek
Joined: 11/09/04
Gender: Male
Re: Caro Advance: 4 Nc3 a6
Reply #238 - 07/29/06 at 21:53:23
Post Tools
OstapBender wrote on 07/29/06 at 17:32:41:
HgMan wrote on 07/29/06 at 15:33:43:
In this case, as I mentioned earlier, Black can do much better than exchanging rooks on c8.  So we put the rook on c4 and see what happens.  I'm reasonably confident that Willempie won't want to exchange rooks on c4, so after 25 Kd3 (forced) Kd7 26 b3 Rc6, White has a more favorable exchange (than on c4), and Black can undouble the pawns.  The semi-open a-file will give Black some counterplay against White's kingside attack, and the Black can help in the queenside play.  I'm still feeling reasonably confident that I can hold...

I understand you must have looked at this more deeply than I have, but I'm not entirely convinced that undoubling the pawns through an exchange on c6 is big enough accomplishment to make 24...Rc4 clearly superior to 24...Kd7.

From what I've examined of 24...Kd7 lines (with the rook exchange coming on c8), it looks to me that Black can hold the position just fine with the maneuver ...Rc4-a4.  I think you guys might be underestimating Black's defensive resources vs. the pawn storm in this line.  If anyone cares to see it, I can post some representative lines supporting 24...Kd7.  If not, fine with me.  I trust you'll make the decision carefully without my help.  Smiley

[BTW, Black might be able to hold in the 24...Rc4 lines as well - in which case I'll admit that 24...Kd7 lines (assuming I'm correct about them) become a moot point.  Good luck!]


Ostap,

Naturally I'd be very interested to see your analysis of 24 ... Kd7.  The main point of these games is to share ideas about the opening (though we're past the opening phase, I suppose).  Most of my reticence surrounding 24 ... Kd7 stems from basic principles more than practical analysis.  Please show me how to escape this game!   Grin
  

"Luck favours the prepared mind."  --Louis Pasteur
Back to top
 
IP Logged
 
Smyslov_Fan
God Member
Correspondence fan
*****
Offline


Progress depends on the
unreasonable man. ~GBS

Posts: 6902
Joined: 06/15/05
Re: Caro Advance: 4 Nc3 a6
Reply #237 - 07/29/06 at 18:09:19
Post Tools
HgMan, 

In correspondence chess as in otb chess, if a line of analysis doesn't work, any good player would back up and search for alternatives.  I was merely pointing out some (serious) problems with your position.  You already have the requisite two weaknesses (the c-file and king-side for White to hope for a win.  I agree with Ostap that you might be overly optimistic about Black's q-side chances.


But I'd love for you to prove me wrong!

(I'm guessing that you may even be looking at the very ugly 24...Rc4 25.Rxc4 dxc4?!/!? in addition to the more normal 25...bxc4.)

Have fun, and I hope you both make the best moves possible!

(I may well take the rook ending with me on vacation to work out some interesting analysis while on the beach.)

Smiley
  
Back to top
 
IP Logged
 
OstapBender
God Member
*****
Offline


There is no spoon.

Posts: 1491
Location: not in Kansas anymore
Joined: 10/16/04
Re: Caro Advance: 4 Nc3 a6
Reply #236 - 07/29/06 at 17:32:41
Post Tools
HgMan wrote on 07/29/06 at 15:33:43:
In this case, as I mentioned earlier, Black can do much better than exchanging rooks on c8.  So we put the rook on c4 and see what happens.  I'm reasonably confident that Willempie won't want to exchange rooks on c4, so after 25 Kd3 (forced) Kd7 26 b3 Rc6, White has a more favorable exchange (than on c4), and Black can undouble the pawns.  The semi-open a-file will give Black some counterplay against White's kingside attack, and the Black can help in the queenside play.  I'm still feeling reasonably confident that I can hold...

I understand you must have looked at this more deeply than I have, but I'm not entirely convinced that undoubling the pawns through an exchange on c6 is big enough accomplishment to make 24...Rc4 clearly superior to 24...Kd7.

From what I've examined of 24...Kd7 lines (with the rook exchange coming on c8), it looks to me that Black can hold the position just fine with the maneuver ...Rc4-a4.  I think you guys might be underestimating Black's defensive resources vs. the pawn storm in this line.  If anyone cares to see it, I can post some representative lines supporting 24...Kd7.  If not, fine with me.  I trust you'll make the decision carefully without my help.  Smiley

[BTW, Black might be able to hold in the 24...Rc4 lines as well - in which case I'll admit that 24...Kd7 lines (assuming I'm correct about them) become a moot point.  Good luck!]
« Last Edit: 07/29/06 at 18:55:43 by OstapBender »  

"If God had wanted us to vote, he would have given us candidates."  -Jay Leno
Back to top
 
IP Logged
 
HgMan
God Member
*****
Offline


Demand me nothing: What
you know, you know

Posts: 2330
Location: Up on Cripple Creek
Joined: 11/09/04
Gender: Male
Re: Caro Advance: 4 Nc3 a6
Reply #235 - 07/29/06 at 15:33:43
Post Tools
Smyslov_Fan wrote on 07/29/06 at 06:45:22:
I've seen Black win from similar positions in the past.  Of course, the most likely outcome is a draw, but White has to be careful now!

HgMan,

You've won me over.  This looks like a nice French endgame.  Congratulations on not only surviving, but thriving!


According to the log, this burst of enthusiasm barely lasted for a quarter of an hour, but I'll take it as a moral victory and a sign that there might just be a crack in the dam.   

That said, I think your quickly rekindled distaste for my position is inspired by a line that starts with a poor move for Black.  In correspondence analysis, we try a line and see if we can get it to work.  If we can, then great; we go back and make sure our opponent can't deviate earlier.  If we can't, we back right up and try to work out the kinks.  In this case, as I mentioned earlier, Black can do much better than exchanging rooks on c8.  So we put the rook on c4 and see what happens.  I'm reasonably confident that Willempie won't want to exchange rooks on c4, so after 25 Kd3 (forced) Kd7 26 b3 Rc6, White has a more favorable exchange (than on c4), and Black can undouble the pawns.  The semi-open a-file will give Black some counterplay against White's kingside attack, and the Black can help in the queenside play.  I'm still feeling reasonably confident that I can hold...
  

"Luck favours the prepared mind."  --Louis Pasteur
Back to top
 
IP Logged
 
HgMan
God Member
*****
Offline


Demand me nothing: What
you know, you know

Posts: 2330
Location: Up on Cripple Creek
Joined: 11/09/04
Gender: Male
Re: Caro Advance: 4 Nc3 a6
Reply #234 - 07/29/06 at 15:17:29
Post Tools
OstapBender wrote on 07/29/06 at 14:24:13:
Smyslov_Fan wrote on 07/29/06 at 13:52:22:
Ostap, 

One, or possibly both of us is tired.  I see HgMan recommending b3 after Kd3.  I don't see White just dropping the d4 pawn.  Which line do you see that does that?

I think HgMan's 28...Kc7 etc. is a continuation of the line suggested  by MNb which begins, after 24...Rc4, with 25.b3 Rc6 26.Rxc6 bxc6 27.Kc3 Kd7 28.Kb4.

Anyway, 25.b3 mentioned by MNb earlier seems to just drop the d4-pawn.  I can imagine that such a line can into consideration base on the idea that Black's back rank vulnerability might prevent this capture, but this doesn't seem to hold up: Black can just grab the pawn.  All key moves come with check, so the back rank never becomes an issue.


We might all be tired.  I missed the 25, and merely assumed that MNb meant 24 ... Rc4 25 Kd3 Kd7 26 b3 Rc6 27 Rxc6 bxc6 28 Kc3, etc.  You're right: I think 25 Kd3 is forced.  25 b3 Rxd4+ 26 Ke3 Re4+ and Kd7 looks fine...
  

"Luck favours the prepared mind."  --Louis Pasteur
Back to top
 
IP Logged
 
OstapBender
God Member
*****
Offline


There is no spoon.

Posts: 1491
Location: not in Kansas anymore
Joined: 10/16/04
Re: Caro Advance: 4 Nc3 a6
Reply #233 - 07/29/06 at 14:24:13
Post Tools
Smyslov_Fan wrote on 07/29/06 at 13:52:22:
Ostap, 

One, or possibly both of us is tired.  I see HgMan recommending b3 after Kd3.  I don't see White just dropping the d4 pawn.  Which line do you see that does that?

I think HgMan's 28...Kc7 etc. is a continuation of the line suggested  by MNb which begins, after 24...Rc4, with 25.b3 Rc6 26.Rxc6 bxc6 27.Kc3 Kd7 28.Kb4.

Anyway, 25.b3 mentioned by MNb earlier seems to just drop the d4-pawn.  I can imagine that such a line came into consideration based on the idea that Black's back rank vulnerability might prevent this capture, but this doesn't seem to hold up: Black can just grab the pawn.  All key moves come with check, so the back rank never becomes an issue.
« Last Edit: 07/29/06 at 20:02:57 by OstapBender »  

"If God had wanted us to vote, he would have given us candidates."  -Jay Leno
Back to top
 
IP Logged
 
Smyslov_Fan
God Member
Correspondence fan
*****
Offline


Progress depends on the
unreasonable man. ~GBS

Posts: 6902
Joined: 06/15/05
Re: Caro Advance: 4 Nc3 a6
Reply #232 - 07/29/06 at 13:52:22
Post Tools
Ostap, 

One, or possibly both of us is tired.  I see HgMan recommending b3 after Kd3.  I don't see White just dropping the d4 pawn.  Which line do you see that does that?
  
Back to top
 
IP Logged
 
OstapBender
God Member
*****
Offline


There is no spoon.

Posts: 1491
Location: not in Kansas anymore
Joined: 10/16/04
Re: Caro Advance: 4 Nc3 a6
Reply #231 - 07/29/06 at 13:48:41
Post Tools
I thought that after 24...Rc4 that 25.Kd3 was more or less forced.

After 25.b3, why not 25...Rxd4+ (26.Ke3 Rd4+)?
  

"If God had wanted us to vote, he would have given us candidates."  -Jay Leno
Back to top
 
IP Logged
 
Page Index Toggle Pages: 1 2 3 [4] 5 6 ... 20
Topic Tools
Bookmarks: del.icio.us Digg Facebook Google Google+ Linked in reddit StumbleUpon Twitter Yahoo