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-   Game 2 - ♔♕♙♘♖♙ - Shaolin Pirates (https://www.mersenneforum.org/forumdisplay.php?f=105)
-   -   White 21 (https://www.mersenneforum.org/showthread.php?t=19148)

cheesehead 2014-02-17 15:19

White 21
 
So, they decided on [url=http://mersenneforum.org/showpost.php?p=367169&postcount=128]20...Rf8[/url]

AKA "20 ... -O"

- - -

Our deadline is next Monday, February 24 10:16 GMT

- - -

Now, the response to 21 Nf6+ could be simply 21 ... Kd8

Perhaps 21 Nd6+ Kd7 22 Nxf7 h5 23 Ng5 Rxf1+ 24 Bxf1. We'd then have the threat Bh3, but Black could answer with ... Nd8. Another threat we'd have is Ne4-c5+.

Oops - gotta go now. More later.

cheesehead 2014-02-18 00:06

[QUOTE=cheesehead;367181]Now, the response to 21 Nf6+ could be simply 21 ... Kd8[/QUOTE]I mentioned that because now the followup 22 Nd7 is no longer a threat, thus Black need not necessarily capture with 21 ... Bxf6.

Similarly, after 21 Nc5, Black is not necessarily forced to respond with 21 ... Bc8 or Ra8 because of the possible d7 fork, but could play 21 ... Bb7.

Candidate moves for us now include not only [B]21 Nf6+[/B] and [B]21 Nd6+[/B] but also:

[B]21 Ndf2[/B] with the idea of bringing this knight into action at g4 or e4 (not to mention connecting our rooks!). This, however, removes a queen-side defender, so has to be analyzed carefully. [B] 21 ... bxc3 22 bxc3 Rb3[/B]. Since we haven't yet moved our N/e4, our c-pawn is not [I]en prise[/I], so we could answer Black's invasion with [b]23 Rfb1[/b].

If 23 ... Rxb1 24 Rxb1 and suddenly it is we, rather than they, with prospects on the b-file.

If 23 ... Rb8 (not 23 ... Rb7 24 Rxb7 Bxb7 25 Nd6+) 24 Rxb8 Nxb8 25 Rb1 it is also we who have b-file threats.
E.g., 25 ... Nbc6 26 Rb6 Bc8 27 Nd6+ Kd7 (not ... Kd8 28 Bxc6 Nxc6 29 Rxc6) 28 Nxc8 Rxc8 (not ... Nxc8 29 Rxc6 or ... Kxc8 29 Bxc6) 29 Ne4 (threatening 30 Nd6 forking two pawns as well as the rook) Nd8 30 Ra6 Nec6 31 Nd6 Rc7 32 Bxc6+ Rxc6 33 Rxa5.

(to be continued)

LaurV 2014-02-18 13:37

This "half castling" (haha, good one, cheesehead!) move is even better than Kf8, and for sure much better than we (I) expected. I don't know why I was thinking that the black king has to go away from the center...

I don't have much time till next weekend... For me it is obvious that one of the Nf6, Nd6 or Nc5 has to be our next move. But which one, no freakin' idea yet. Also, Bd2 might be very good against bxc3 adventure, if they beat, we place the bishop in c3, a very strong position, and don't separate the a/b pawns.

cheesehead 2014-02-19 13:51

Besides 21 ... bxc3, other responses to [B]21 Ndf2[/B] could be 21 ... Nd5, 21 ... Nf5, 21 ... h5 and 21 ... g5.

[B]21 ... Nd5 22 Bd2[/B] and Black can begin freeing himself with 22 ... f5. 23 exf6 Bxf6 (not ... Nxf6 24 Nxf6+ Rxf6 26 Bxc6+) 24 Nxf6 Rxf6 25 Bxh6 and we're a pawn up, but Black is freer than he was 5-6 moves earlier. But Black could instead be patient and prepare with 22 ... Nce7 before pushing his f-pawn. Then maybe 23 Ng4 h5 24 Ngf6+ Bxf6 (not ... Nxf6 25 exf6 fork) 25 exf6 and that pawn sticks in Black's craw at f6, but Black surely must have something better than this line. Material would still be even.

[B]21 ... Nf5 22 Bd2[/B]. Black's N/f5 seemingly can't do much -- we control the dark squares he could reach -- but would be a good outpost that's annoyingly in our way on the king-side and center. We can't readily push it away: 23 g4 Nh4.

[B]21 ... h5[/B] takes the looseness out of that pawn, but we can proceed with [b]22 Nd6+ Kd7 23 Nfe4 Nd8 24 Nc5+[b]. [B]21 ... g5[/B] has the same problem: [B]22 Nd6+[/B] etc. So Black wouldn't choose either pawn move at this point.

So, I've now decided that 21 Ndf2 isn't better for us than [B]21 Nd6+[/B].

My vote:
[b]21 Nd6+[/b] -- 5
[b]21 Nfd2[/b] -- 2
[b]21 Nf6+[/b] -- 1
[b]21 Nc5[/b] -- 1

WMHalsdorf 2014-02-19 16:07

My problem with 21.Nd6+ Kd7 22. Nxf7 is Black's reply of Nf5.
A deep analysis of Nc5 is called for in this position since the Knight can't be easily be removed and disrupts Black's movements on the queen's side and makes it possible to capture the pawn on c4.

LaurV 2014-02-19 16:42

[QUOTE=cheesehead;367301]
<snip>
[B]21 Nfd2[/B] -- 2
<snip>
[B]21 Nc5[/B] -- 1
[/QUOTE]
You wanted to write Ndf2, as there is no horse in f. Which is not a bad move, in fact. Ndf2, Nd5, Bd2 it is something I like very much for us, assuming they don't find anything better instead of Nd5, we would stay quite convenient. Also, after Ndf2, Nd5, we can do Ng4, even better. The question is only if Nd5 is their best reply. It may not be.

Also, my feeling is that you are not fair with Nc5**, giving it only one point. Nc5 is a quite aggressive move, and I like it a lot, better than Nd6 or Nf6. You are, however, right in placing Nd6 better than Nf6. After they moved that rock, 21 Nf6 doesn't make too much sense, after Kd8, we don't have much to do, and they are not forced to take the horse. Bad for us. I mean, not bad, but not the happy end we want. 21 Nd6 on the other hand puts some pressure on f7, so it is much better in my scale. Back to 21 Nc5, where do they put the bishop? If I look more to this move, I start to like it more. After 21 Nc5, bishop somewhere, or rook defends bishop, 22 Bd2, we might get clean with the queen side and their king is still in the middle, not castled. I love this part. I think after all, their rook move was a mistake. Not a big one, but they could do better.

My vote yet to come.

**edit: I posted that fragment before seeing WMH's comment. This window was opened for few hours already, during I was mumbling around, and you WMH cross-posted in between, and it seems that you also have seen the potential of Nc5. We have to analyze deeper here.

cheesehead 2014-02-20 09:01

[QUOTE=WMHalsdorf;367305]My problem with 21.Nd6+ Kd7 22. Nxf7 is Black's reply of Nf5.

A deep analysis of Nc5 is called for in this position since the Knight can't be easily be removed and disrupts Black's movements on the queen's side and makes it possible to capture the pawn on c4.[/QUOTE]Right-o on both. I was much too hasty when finishing up my preceding post.

[QUOTE=LaurV;367309]Also, my feeling is that you are not fair with Nc5**, giving it only one point.[/QUOTE]Right-o.

I withdraw my previous move votes.

[quote]Back to 21 Nc5, where do they put the bishop?[/quote]No matter where, they're not going to play Nf5 soon without losing a knight, unless they first stash the N/c6 on the edge somewhere for safety. (If 21 ... Bb7, the N/c6 is not yet safe because of our possible Nxb7.)

Also, Nc5 prevents their king from coming to the defense of their N/c6 in a single move.

[quote]If I look more to this move, I start to like it more. After 21 Nc5, bishop somewhere, or rook defends bishop[/quote](the latter of which places the rook on the long diagonal reaching from g2)

[quote]We have to analyze deeper here.[/quote]Yes, and we still have four days to do so.

WMHalsdorf 2014-02-20 20:31

Looking at the rook moves 21.... Ra8 or Rb6
22. Nxa6 Rxa6 23. Bxc6+ Rxc6 24. cxb4 axb4 25. Bd2 gives us a win
21.... Ra8 or Rb6 22. Nxa6 Rxa6 23. Bxc6+ Nxc6 24. Bd2 making way for Ne3 then Nxc4

cheesehead 2014-02-21 00:28

[QUOTE=WMHalsdorf;367384]21.... Ra8 or Rb6 22. Nxa6 Rxa6 23. Bxc6+ Nxc6 24. Bd2 making way for Ne3 then Nxc4[/QUOTE]except 24 ... Na7(or b8 or d8) 25 Ne3 Rc6 26 Ng4 h5 and material's still even.

Scenario (undoubtedly overlooking better moves for Black along the way):
[B]21 Nc5 Ra8(or b6) 22 Nxa6 Rxa6 23 Bxc6+ Nxc6[/B] 24 Nf2 f5 25 exf6 Rxf6 (not 25 ... Bxf6 26 Bxh6) 26 Ne4 (threatening Nd6+ and Nxc4) Rxf1+ 27 Rxf1 Ne7 (not ... Ke7 28 Nd2 wins the c-pawn) 28 Bf4 Nc8 29 Nc5 Rc6 30 Re1 Ke7 31 Nb7 Ra6 32 Bc7 Ra7 33 Nc5 Rxc7 34 Nxe6 Ra6 35 Nxg7+ Kf7 36 Ne6 Re7 37 Nd8+ Ke8 38 Rxe7+ Nxe7 (not ... Kxe7 39 Nc6+) 39 Nb7 Nc6 40 Nd6+ K-moves 41 Nxc4 and we're two pawns up.

WMHalsdorf 2014-02-21 04:17

[QUOTE=cheesehead;367398]except 24 ... Na7(or b8 or d8) 25 Ne3 Rc6 26 Ng4 h5 and material's still even.
[/QUOTE]
If 24 ... Na7(or b8 or d8) then 25. cxb4
[QUOTE=cheesehead;367398]Scenario (undoubtedly overlooking better moves for Black along the way):
[B]21 Nc5 Ra8(or b6) 22 Nxa6 Rxa6 23 Bxc6+ Nxc6[/B] 24 Nf2 f5 25 exf6 Rxf6 (not 25 ... Bxf6 26 Bxh6) 26 Ne4 (threatening Nd6+ and Nxc4) Rxf1+ 27 Rxf1 Ne7 (not ... Ke7 28 Nd2 wins the c-pawn) 28 Bf4 Nc8 29 Nc5 Rc6 30 Re1 Ke7 31 Nb7 Ra6 32 Bc7 Ra7 33 Nc5 Rxc7 34 Nxe6 Ra6 35 Nxg7+ Kf7 36 Ne6 Re7 37 Nd8+ Ke8 38 Rxe7+ Nxe7 (not ... Kxe7 39 Nc6+) 39 Nb7 Nc6 40 Nd6+ K-moves 41 Nxc4 and we're two pawns up.[/QUOTE]
This looks interesting.

cheesehead 2014-02-21 05:39

[QUOTE=WMHalsdorf;367405]If 24 ... Na7(or b8 or d8) then 25. cxb4
[/QUOTE]When I consider all the moves I've overlooked in this one game's analysis, until someone else pointed them out, I tremble at the prospect of ever playing OTB again. :-)

LaurV 2014-02-21 05:56

Same here, when I play with friends face to face, I overlook many moves and I only do a little better than an average player. Usually, when I lose, it is because I make stupid mistakes during the opening phase. Mostly I win, but that is not because I am good player, but because my friends do the same mistakes I do.

When you are at home and allowed to think for a week, the things are different.

WMHalsdorf 2014-02-21 19:20

21 Nc5 Ra8(or b6) 22 Nxa6 Rxa6 23 Bxc6+ Nxc6 24 Nf2 f5 25 exf6 Rxf6 (not 25 ... Bxf6 26 Bxh6) 26 Ne4 (threatening Nd6+ and Nxc4) Rxf1+ 27 Rxf1 Ne7 (not ... Ke7 28 Nd2 wins the c-pawn) 28 Bf4 Nc8 29 Nc5 Rc6 30 Re1 Ke7 31 Nb7 Ra6 32 Bc7 Ra7 33 Nc5 Rxc7 34 Nxe6 Ra6 35 Nxg7+ Kf7 36 Ne6 Re7 37 Nd8+ Ke8 38 Rxe7+ Nxe7 (not ... Kxe7 39 Nc6+) 39 Nb7 Nc6 40 Nd6+ K-moves 41 Nxc4 and we're two pawns up.

34.... Bxd4+ 35. Nxd4+ with the goal of Re5 it looks like a long drawn out win.

cheesehead 2014-02-22 01:19

Just noticed a typo in move 34 of my post #9 scenario:
[QUOTE=WMHalsdorf;367478]21 Nc5 Ra8(or b6) 22 Nxa6 Rxa6 23 Bxc6+ Nxc6 24 Nf2 f5 25 exf6 Rxf6 (not 25 ... Bxf6 26 Bxh6) 26 Ne4 (threatening Nd6+ and Nxc4) Rxf1+ 27 Rxf1 Ne7 (not ... Ke7 28 Nd2 wins the c-pawn) 28 Bf4 Nc8 29 Nc5 Rc6 30 Re1 Ke7 31 Nb7 Ra6 32 Bc7 Ra7 33 Nc5 Rxc7 34 Nxe6 [strike]Ra6[/strike][/QUOTE]Ra7

But[quote]34.... Bxd4+[/quote]is much better than that!

- - -

You guys have convinced me about the superiority of [B]21 Nc5[/B].

However, I'm dubious about 23 Bxc6+ as a followup -- I can't even recall how it got into my scenario as a bolded main line move! I think our B/g2 is better than their N/c6.
23 Bd2 and 24 Ne3 would look better, if it weren't for 23 ... Nf5.

- - -

My vote as of now:

[B]21 Nc5[/B] -- 5
[B]21 Ndf2[/B] -- 3
[B]21 Bd2 [/B]-- 3
[B]21 Nf6+[/B] -- 0
[B][B][B]21 Nd6+[/B] [/B]--[/B] 0

WMHalsdorf 2014-02-22 03:04

[QUOTE=cheesehead;367496]Just noticed a typo in move 34 of my post #9 scenario:
Ra7

Butis much better than that!

- - -

You guys have convinced me about the superiority of [B]21 Nc5[/B].

However, I'm dubious about 23 Bxc6+ as a followup -- I can't even recall how it got into my scenario as a bolded main line move! I think our B/g2 is better than their N/c6.
23 Bd2 and 24 Ne3 would look better, if it weren't for 23 ... Nf5.
[/QUOTE]
if 23... Nf5 then 24. g4 chases it back.

21 Nc5 -- 5
21 Bd2 -- 3
21 Ndf2 -- 2
21 Nf6+ -- 0
21 Nd6+ -- 0

cheesehead 2014-02-22 06:03

[QUOTE=cheesehead;367496]However, I'm dubious about 23 Bxc6+ as a followup -- I can't even recall how it got into my scenario as a bolded main line move![/QUOTE]_Now_ I remember. It's to remove a defender of b4. If Black recaptures with the other knight instead of the rook, then Ne3 nabs the c4-pawn.

LaurV 2014-02-22 12:19

Ok. My vote for 21:

Nc5 - 5
Bd2 - 4
Ndf2 - 3
Nd6 - 1
Nf6 - 0

The tandem Nc5+Bd2 is very strong path for us now, and it may be how we actually win the game. The order may not be really important, as they don't have a good reply to Bd2 either, which would forbid us to play 22 Nc5, nor they have a very strong threat. I prefer 21 Nc5 because they are forced to move/defend the bishop, so this path is safer for us in case we missed something.

Now, should we play Nc5, or wait till Sunday, to deprive them of one weekend? hehe (I am sadistic now!)

I think we should play it.

Edit: for the path discussed above: [B]21 Nc5 Ra8[/B], then [B]22 Bd2[/B] is still good! in fact Ra8 is even better (!for us!) than Rc6, because black gave up the column b, and the rook now links the horse! What do they move 22...?? Because bxc3 is [STRIKE]really bad[/STRIKE] suicide! without that rook, and there is nothing to be done, maybe Bc8 only, but too defensive. Therefore, 21...Bc8 or Bb7 seem to be much better moved for them now than defending with the rook. And so, with Ne3 we develop the horse, as one of you already mentioned, and we may get the c4 pawn for free.

I think I will play Nc5 now, give them the weekend to think about. Let's be fair play and don't cut deeper into their wounds while they are already in the sink hole :razz:

cheesehead 2014-02-22 18:06

[QUOTE=LaurV;367544]I think I will play Nc5 now[/quote]Fine.
[quote]cut deeper into their wounds while they are already in the sink hole :razz:[/QUOTE]Few would think of that combination.

- -

If 21 ... Ra8 or Rb6, Black would be indicating reluctance to move the B, so we could do something other than 22 Nxa6 immediately, because the B/a6 probably won't run away if it's already passed that up once.

We could then play 22 Bd2 (I've seen the light about ... bxc3, Bxc3 now, LaurV!) & 23 Ne3 first, then 24 Nxa6 & 25 Nxc4. Of course, I've skipped Black moves 22 and 23 there, so have to consider what Black could do on 22 and 23 to prevent (not just delay, such as ... bxc3) 25 Nxc4.

22 ... h5 and 23 ... Bh6, that's what.
[b]21 ... Ra8 (or Rb6) 22 Bd2 h5 23 Ne3 Bh6 24 Nxa6 Bxe3+ 25 Bxe3 Rxa6[/b]

So, attack c4 a different way: 22 Rf2, 23 Bf1, 24 Nxa6, 25 Bxc4
What can Black do on 22 and 23 to prevent (not just delay) 25 Bxc4?

21 ... Ra8, then bring over the other knight with 22 ... Nc8 and 23 ... Nb6 -- except for our 23 Bxc6+ interruption of [i]that[/i] scheme.

Oh, here it is:

[b]21 ... Bb7 22 Rf2 Nd5 23 Bd2 a5 24 Bf1 Nb6 25 Ne3 Bh6[/b] but we've succeeded in bringing two attacking pieces to bear on c4 versus one defender. [b]26 Nxc4[/b]. We got it.

Then maybe :-) 26 ... Bxd2 27 Nd6+ Ke7 28 Rxd2 Ba8 29 Na6 Rd8 30 Bb5 Na7 ... and I don't know what.

cheesehead 2014-02-23 01:21

[QUOTE=cheesehead;367562]
[B]21 ... Bb7 22 Rf2 Nd5 23 Bd2 a5 24 Bf1 Nb6 25 Ne3 Bh6[/B] but we've succeeded in bringing two attacking pieces to bear on c4 versus one defender. [B]26 Nxc4[/B]. We got it.[/QUOTE]Why [b]21 ... Bb7[/b]?
If 21 ... Bc8 22 Rf2 Nd5 23 Bd2 a5 24 Ne3 but now 24 ... Nb6 is not feasible because of 25 Bxc6+. If instead 24 ... Nce7, the c4 pawn falls anyway: 25 Nxc4.

LaurV 2014-02-23 09:10

[QUOTE=cheesehead;367587] [B]21 ... Bb7[/B]?
[/QUOTE]
I also think that Bb7 is the best from the 4 moves they can play now (the other 3 are Rb6, Ra8, Bc8, to save the bishop). Anyhow, we still can play Bd2 after. We stay quite good now.

cheesehead 2014-02-23 23:59

Something I forgot to do earlier: count tempos needed to achieve the subgoal of taking the c4 pawn. This may seem unnecessary after we've already laid out scenarios, but it might possibly help (me, at least :-) notice something overlooked.

(BTW, I don't recall ever having done this before the endgame phase in any previous game. I'll have to keep it in mind for possible future middlegame use.)

I'm going to count only the preparation tempi, not the actual c4 capture which should be simply a sequence of successive captures at the end.

For us:
Move N/d1 to e3, and B/g2 to f1, to have two attackers on c4: four tempi. Remove B/a6 defender if it's still there: one tempo. Total: 4-5.

For Black:
Defend B/a6, or move it: one tempo. Move N/e7, through either c8 or d5, to b6 for defending c4: two tempi. Either defend N/c6 or move it off the long diagonal: one tempo. However, Bb7 would simultaneously defend both B and N, so don't count that tempo twice. Move B/g7 to h6 for taking out our N/e3: two tempi. Total: 4-6.

However, some Black moves might interfere with other moves, such as (a) Rb6 to defend the B/a6 and also placing N/e7 on b6 to defend the c4-pawn or (b) moving Bc8 to escape attack and also moving N/e7 through c8, rather than Nd5, to reach b6. That means Black will probably not move Rb6, and must move Nd5 if the B/a6 retreats to c8.

Further, in order to retain B/g2 threats to capture a N on d5 or c6, we should leave the B/g2 where it is until the last moment, so Bf1 would be the last move of our sequence.

- -

So, how to use this?

First, on move 21:
If Black plays [B]21 ... Ra8 or Rb6[/B], then we'll (probably) have to spend the Nxa6 tempo, for a total of five.

But [B]21 ... Bb7[/B] would accomplish two things (defend B/a6, defend N/c6) with a single tempo. Then, once Black plays Nc8 or Nd5, we could remove the only remaining knight defender with Nxb7, same tempo as Nxa6 would have taken. But Black can probably avoid ever exposing the N/c6 to capture by the B/g2.

So, logical Black move 21 is [B]21 ... Bb7[/B] -- Oh, you guys already figured that out.

Move 22:
On moves 22 and 23, we can bring one attacker to bear on c4 -- the Ne3, because we want to leave Bf1 until last. So, [B]22 Bd2[/B] has merit over 22 Rf2.

Therefore, Black can't afford to waste any time bringing his N/e7 to defend c4. But 22 ... Nc8 isn't feasible because of 23 Nxb7 Rxb7 24 Bxc6+

So it'd be [B]22 ... Nd5[/B]

Now 23 Bxd5 would eliminate a potential c4 defender ... but that just would allow a different defender to appear: 23 ... exd5.
If then 24 Ne3 to attack the d5-pawn, 24 ... Ne7 defends it twice, and we could remove only one of those defenders with 25 Nxb7. Then after 25 ... Rxb7 we've basically just helped Black un-crowd his queen-side while winning no material.
We could then switch our attack to the b-pawn with 26 cxb4 axb4 27 Nc2 but 27 ... b3 squelches that.
We could then switch again to attack d5: 28 Na3 intending 29 Nb5 and 30 Bb4 pinning the N/e7 against the R/f8. Then repositioning with 31 Ba3 and 32 Nc3 gets us to where we can take out the N defender and capture the d5 pawn on successive moves. But that leaves out Black's 28, 29, 30, 31 and 32, which undoubtedly could be used not only to adequately defend d5, but also do other mischief.
So 23 Bxd5 looks like a dead-end unless one of you see something better.

[B]23 Ne3[/B] allows instant neutralization: [B]23 ... Nxe3 24 Bxe3[/B], but that would also revive our old threat on c6: 25 Nxb7 Rxb7 26 Bxc6+. So, Black would have to double-defend b7 with [B]24 ... Nd8[/B]. Now c4 is undefended, but we don't have time for 25 Rf2 and 26 Bf1 because of 25 ... Bxg2. So, we have to do [B]25 Nxb7[/B] first. [B]25 ... Nxb7[/B] (not ... Rxb7) [B]26 Rf2 Nd8 27 Bf1 Rc8[/B]
Now [B]28 Bd2[/B] would revive our attack on Black's a&b pawns.

Black could defend a5 with 28 ... Nb7 but that wouldn't help b4: 29 cxb4 axb4 30 Bxb4. So, Black does [B]28 ... bxc3[/B] first. [B]29 Bxc3 Nb7[/B] and Black has defended both pawns from our bishops' attacks.

30 Rc1 would threaten to capture on c4 (or c3) after 31 Bd2. Black could delay that with 30 ... f6 threatening fxe5 and bxe5. 31 exf6 Bxf6 unleashes that bishop, so better would be to just defend e5. 31 Re2 would block our light-squared bishops' attack. So, we need to move a different rook on move 30.

[b]30 Rc2[/b], then if 30 ... f6 31 Re1 fxe5 32 dxe5, it's possible to continue Black's attack on e5 with 32 ... Rf5 but 33 g4 Rg5 34 h3 Rc5 35 Bd4 stops that (if 35 ... Bxe5 36 Bxc5 Nxc5 37 Bxc4).

What else might Black try on move 30?

There may be some way for Black to deviate from the bolded line above, but I hope all our bolded moves are so forcing that they leave Black no spare time.

- - -

Given my past record about seeing moves in this game, the chances of the game's playing out just as I've outlined are probably nil. :-(

WMHalsdorf 2014-02-24 02:14

[edit by laurv: I cut the full text quote to the previous post, a bit too long for just one line reply :D]

23. Nxb7 Rxb7 24. Ne3 and the pawn on c4 falls.

cheesehead 2014-02-24 11:56

[QUOTE=WMHalsdorf;367667]
23. Nxb7 Rxb7 24. Ne3 and the pawn on c4 falls.[/QUOTE]Right-o.

I forgot that just as soon as Black plays [U]either[/U] 22 ... Nc8 [U]or[/U] [B]22 ... Nd5[/B], his N/c6 has only one defender. In the latter case, his N/d5 is the shield not only for his N/c6, but also for his R/b7.

(Well, at least I included the qualifier.)

- - -

So, is
[b]21 ... Bc8[/b]
now the main line?

LaurV 2014-02-24 14:49

Very interesting variants, and very good posts. I saw them today, but I was at job. Went through them right now.

Well, as you all said/agreed, bxc3 is out of discussion, we take the bishop, black is gone. If cxb2, then Rb1, nothing black can do to save the pawn or the game (they have to move the rook and b3 is the only place where they don't lose so big). So, bxc3 is suicide.

There are only 4 moves available which tempt to save the bishop:

For 21..Ra8 - the weakest from the four, 22.Bd2, and black has no move. Their (most probably) best: 22..Nd5 23.Ne3, we get a second pawn (either the one in c4, or in d5 after exchanging the horses), so he is forced now to play the horse back, or better to guard it with Nc6e7. Then we can safely do 24.cxb4, ad his horse is linked with the rook. This is win for us, with material advantage and two free pawns.

21...Rb6, a bit better, as now the rook is not linked. Yet, after 22 Bd2 Nd5, with 23 Bxd5, exd5 black can't defend the pawn in d5, 24 Ne3, gone. Better would be 22...Nf5, but then 23.cxb4 axb4 24 Nxa5 Rxa5 Bxb4, attack on f8 rock, we are very good positional and get a small material advantage, we still can exchange the bishop in g2 for the horse in c5, or they can beat with the horse on b4, or push c3, but this changes nothing. We rule there.

I consider 21...Bc8 weaker than Bb7, because this links (indirectly) the horse in e7. This can't be moved now to f5 without losing the one in c6. An interesting (but risky, and a bit stupid) play for black would be to beat Nxd4, somewhere down on this tree, then push c3, and we may be forced to give back the figure, otherwise they transform (or take our rook from a1).

The 21...Bb7 is not totally excluded. Even with WMH's variant (which is very good move for white by the way, nice find!), after 24 Ne3, Rd7, 25 Nxc4 Ke7, and black is well guarded, they can bring the second rook to the game very easy (in one move!), and they have 3 pieces beating on the b4 pawn. I would say that this is the most difficult variant for us. After cxb4, they do Nxd4 and recover the pawn. If we now take Nxa5 to keep the score, then Rf8d8, black is strong, we have a pawn more, but our e5 is not guarded and they can take it. Also, Nxb4 instead of Nxd4 is good for them. Indeed this variant is most difficult to penetrate, for us.

So, we have to think for both of the[B] Bb7[/B] [B][U]AND[/U][/B] [B]Bc8[/B] replies, if we want to think in advance. All other moves are loss for black, most probably.

WMHalsdorf 2014-02-24 14:51

[QUOTE=cheesehead;367697]Right-o.

I forgot that just as soon as Black plays [U]either[/U] 22 ... Nc8 [U]or[/U] [B]22 ... Nd5[/B], his N/c6 has only one defender. In the latter case, his N/d5 is the shield not only for his N/c6, but also for his R/b7.

(Well, at least I included the qualifier.)

- - -

So, is
[b]21 ... Bc8[/b]
now the main line?[/QUOTE]

At first glace one would think so but it is probably the worst since we get to keep our knight on c5 hindering all of Black's movement on queen's side leading to a capture of the c4 pawn after 22. Bd2 , 23. Ne3 , 24. Nxc4 and a possinle folloe up with 25. Nd6
They also lose the pawn with 21... Bc8 22. Bd2 h5 23. Ne3 Bh6 24. Nxc4 Bxd2 25. Nxd2

LaurV 2014-02-24 15:20

[QUOTE=WMHalsdorf;367709]
They also lose the pawn with 21... Bc8 22. Bd2 h5 23. Ne3 Bh6 24. Nxc4 Bxd2 25. Nxd2[/QUOTE]
We can do better here. They can't play the king side, after h5, 23.Bg5, and end game. They can't do much, beside (23-24) exchanging the pawn in c3, 24...Rb6, 25 Ne3, they are totally close, we stay soooo good, and c4 is under siege, and can't be saved. They may try a "desperate" 23 (or 24) Nxe5, dxe5 Bxe5, which actually does not seem too bad for them, they play with 2 pawns against a horse, so (26?) Re1, Bc7, apparently quite good for black, his only problem is that the a/c pawns are too far apart and can't be efficiently guarded. But he may link our horses easy, if we dare to develop Ne3... But well, we don't do Ne3 now! We do Bf6(!) Bb6 Re5, we stay much better now.

WMHalsdorf 2014-02-24 18:24

[QUOTE=LaurV;367711]We can do better here. They can't play the king side, after h5, 23.Bg5, and end game. They can't do much, beside (23-24) exchanging the pawn in c3, 24...Rb6, 25 Ne3, they are totally close, we stay soooo good, and c4 is under siege, and can't be saved. They may try a "desperate" 23 (or 24) Nxe5, dxe5 Bxe5, which actually does not seem too bad for them, they play with 2 pawns against a horse, so (26?) Re1, Bc7, apparently quite good for black, his only problem is that the a/c pawns are too far apart and can't be efficiently guarded. But he may link our horses easy, if we dare to develop Ne3... But well, we don't do Ne3 now! We do Bf6(!) Bb6 Re5, we stay much better now.[/QUOTE]
It's suicide for Black to play Nxe5 after Bd2 because the best reply is cxb resulting in a passed pawn for us.


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