White 21

cheesehead · 2014-02-17, 15:19

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. :-)

2014-02-17, 15:19	#1
cheesehead "Richard B. Woods" Aug 2002 Wisconsin USA 2²×3×641 Posts	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.

2014-02-19, 13:51	#4
cheesehead "Richard B. Woods" Aug 2002 Wisconsin USA 2²×3×641 Posts	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 Last fiddled with by cheesehead on 2014-02-19 at 13:59 Reason: Xyzzy's doing the thing that messes up formatting again.

2014-02-19, 16:42	#6
LaurV Romulan Interpreter "name field" Jun 2011 Thailand 2·5,179 Posts	[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. Last fiddled with by LaurV on 2014-02-19 at 16:51

2014-02-20, 09:01	#7
cheesehead "Richard B. Woods" Aug 2002 Wisconsin USA 2²×3×641 Posts	[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. Last fiddled with by cheesehead on 2014-02-20 at 09:14*

2014-02-21, 00:28	#9
cheesehead "Richard B. Woods" Aug 2002 Wisconsin USA 2²·3·641 Posts	[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. Last fiddled with by cheesehead on 2014-02-21 at 00:51

2014-02-18, 00:06	#2
cheesehead "Richard B. Woods" Aug 2002 Wisconsin USA 1111000001100₂ Posts	[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)

2014-02-18, 13:37	#3
LaurV Romulan Interpreter "name field" Jun 2011 Thailand 24166₈ Posts	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.

2014-02-19, 16:07	#5
WMHalsdorf Feb 2005 Bristol, CT 1001₈ Posts	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.

2014-02-20, 20:31	#8
WMHalsdorf Feb 2005 Bristol, CT 201₁₆ Posts	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

2014-02-21, 04:17	#10
WMHalsdorf Feb 2005 Bristol, CT 3³×19 Posts	[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.

2014-02-21, 05:39	#11
cheesehead "Richard B. Woods" Aug 2002 Wisconsin USA 2²×3×641 Posts	[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. :-)

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
White 20	cheesehead	Game 2 - ♔♕♙♘♖♙ - Shaolin Pirates	23	2014-02-13 08:04
White 19	cheesehead	Game 2 - ♔♕♙♘♖♙ - Shaolin Pirates	12	2014-01-31 20:14
White 18	cheesehead	Game 2 - ♔♕♙♘♖♙ - Shaolin Pirates	16	2014-01-24 22:11
White 17	cheesehead	Game 2 - ♔♕♙♘♖♙ - Shaolin Pirates	22	2013-12-20 18:11
White 16	LaurV	Game 2 - ♔♕♙♘♖♙ - Shaolin Pirates	15	2013-12-08 10:49