< Earlier Kibitzing · PAGE 2 OF 2 ·
|Jun-20-09|| ||goodevans: <Lambda>, In the line we both chose it's essential to attack the pinned black rook with the R(d2) before attacking with the f-pawn. Otherwise black can wriggle out of it with ... Re1+.|
|Jun-20-09|| ||Magic 8 Ball: Correct me if I'm wrong, but 22... Kg7? sets up 23 Nc7 Rb8 24 Ne8+ losing the rook on f6.
Better would have been 22... a6 or Rb6, which loses less material.|
|Jun-20-09|| ||vaskokibika: maybe there are several solutions here.
OTB I would play my line:
20. Nc7 Rb8
21. f4 Rf5
22. Nd5 Qxc3
23. Ne7+ Kh8
24. bxc3 Rf6
|Jun-20-09|| ||CHESSTTCAMPS: Material is even, but white is ahead in development and has much more activity. Furthermore, the pin on the Re5 suggests that the black queen can be overloaded. It is also evident that white's knight can be redeployed with tempo:|
... and the rest of the combination flows naturally:
21.Ne8! and now:
A. 21... Qe7 (or Qe6) 22.f4! Qxe8 23.Qxe5 and white's exchange advantage wins easily.
A.1 22... Re1+ 23.Kf2 Qxe8 (Rxa1 24.Qg7#) 24.Rxe1 is even easier for white.
B. 21... Qh8 22.Rd8! leaves no good defense against the threat of 23.Nd6, e.g. 22...Re2 23.Qxh8+ Kxh8 24.Nd6 Kg7 25.Rxc8 Rxc8 26.Nxc8 Rxb2 27.Nxa7
B.1 22.Re2 Rxe2 23.Nf6+ Qxf6 24.Qxf6 Be6 should also win for white but gives black much more activity.
B.1.2 23... Kg7? 24.Ng4+ f6 25.Qxf6+ Kg8 26.Nh6#
C. 21... Qg5 22.f4 wins
D. 22... Qf5 23.Re2! f6 24.Nxf6+ Qxf6 25.Qxe5 wins easily.
Very pretty, but straightforward. Not the wide range of possibilities that were in yesterday's puzzle.
|Jun-20-09|| ||CHESSTTCAMPS: Well, I can't argue with the simplicity of the game continuation. I guess many of us were looking for a flashier way to win.|
|Jun-20-09|| ||UnsoundHero: Black resigned because of 23...Ne6 24 Ne8+ Kf8 25 Rxc8 Rxc8 26 Nxf6.|
|Jun-20-09|| ||remolino: Seems like motif must be to exploit the poor placing of Black's rook. Other motifs: Black's back rank, pressure on long diagonal g2-a8, perhaps even pressure on f7.
After 20.Nc7 Rb8 forced, 21. f4 Rf5 (21...Re6, 22. Nc7 ), 22. Qxf6 Rxf6|
23. Nd5 works in all variations except one of them it seems, e.g.,
23... Rf5 or Rc6, 24. Re7+
23... Ra6 or Rb6, 24. Re7+ Kg7 25. Rd8
But if 23...Re6 I could no longer make progress
After 22.Qf6 Rxf6 I would have played then 23. Rd8 with pressure
After 30 minutes, it is time to see what the solution is...
I am counting this a puzzle solved since through transposition of moves I got to same concept, and all moves are forced. After 23.Rd8 in my line, Black is in a bind: cannot unpin the knight because of N check and the white rook on a1 will join the attack.
A Saturday for me.
To summarize, do you all agree that this order of moves works?
20.Nc7 Rb8, 21. f4 Rf5, 22. Qxf6 Rxf6, 23. Rd8!
|Jun-20-09|| ||randomsac: I was trying to figure out how Nc7 could get something going. The combo was awesome, effectively forking a rook and a rook fork. This was definitely worth seeing.|
|Jun-20-09|| ||johnlspouge: Saturday (Very Difficult)
V Neverov vs A I Hamed, 1999 (20.?)
White to play and win.
Material: Even. The Black Kg8 has 2 legal moves, g7 and h8, both on the a1-h8 diagonal. The White Qc3 X-rays both squares, while pinning Re5 to Qf6. The pin has only limited effectiveness, because Re5 can escape to either e6 or f5, protecting Qf6. The White Rd2 commands the open d-file and the invasion square d8. The Qf6 is therefore overburdened, protecting d8 and Re5. The White Ra1 is ready to form a battery or reload on the d-file. The White Bg2 pins Pb7 to Ra8, which is loose, so Bc8 is burdened with Pb7. The White Nb5 requires activation. The White Kg1 is vulnerable to …Re1+ and …Qxf2+, neither of which has any venom.
Candidates (20.): Nc7
20.Nc7 Rb1 [else, drop Ra1]
21.Ne8 (safely threatening 22.Nxf6+, because Qc3 pins Re5 to Qf6)
Black must move Qf6, permitting White to pin Re5 to something more substantial than Qf6, namely, the mate threat Qc3-g7#. White’s real threat is therefore 22.Re2, with an X-ray defense of Ne8 and a double attack on Re5.
21…Qe7 [or other Q moves]
[f6 23.Nxf6+ Qxf6 24.Qxe5] [R moves 23.Qg7#] [else, Rxe5]
23.f4 (threatening 24.fxe5)
Unlike the previous turn, the White Re2 now prevents …Re1+, so the threat 24.Qg7# completely immobilizes the Black Re5. White captures 24.fxe5 and wins at least the exchange.
Although Toga finds 20.Nc7 first and sticks to it for a long time, it eventually prefers 20.f4 (+3 P) over 20.Nc7 (+2 P).
|Jun-20-09|| ||LaFreak III: 20.Nc7 is the best|
|Jun-20-09|| ||johnlspouge: < <LaFreak III> wrote: 20.Nc7 is the best >|
...not according to Toga.
< <CHESSTTCAMPS> wrote: Well, I can't argue with the simplicity of the game continuation. I guess many of us were looking for a flashier way to win. >
I am self-critical, but not masochistic :)
I would defend my choice of 20.Nc7 as logical, given my positional analysis of the weakness of the a1-h8 diagonal and its attendant mating possibilities. I actually had some trouble finding the threat after 22.Rd8, but 23.Nd6 24.Rxc8 is a potent menace.
All said, I see the game continuation as preferable to 20.Nc7.
|Jun-20-09|| ||Stormbringer: I saw the motifs of the pinned rook against the queen, and the advance of the knight to c7, but didn't see or understand Rd8 or Kg7.
I'd thought maybe move one of white's rooks to attack the black rook and force it to move, but then the straight queen swap wasn't what I thought we were after. I kind of get that the idea was to chase black's pieces onto 'bad squares' (or something like that) and thus put him into zugzwang, but this is way out of my league. :D|
|Jun-20-09|| ||kevin86: A deft finish! White threatens one rook by attack 24 ♘xa8 and the other by the fork, 24 ♘e8+. Black is lost.|
|Jun-20-09|| ||playground player: All I can say about this puzzle is,
|Jun-20-09|| ||Jimfromprovidence: If black tries to forego undoing the pin and play 22…Rb6 instead of 22…Kg7, it takes a little longer but white ends up in the same place. |
Here is the position after the continuation 22…Rb6 23 Nc7 Rb8.
click for larger view
Black is doing what he can to escape but white can reinforce his attack with 24 Re1. Black likely has to play 24…Kg7 in response.
Now, 25 Ree8 wins a piece.
click for larger view
|Jun-20-09|| ||agb2002: The dark squares (and the pieces on them) around the black king and Black's back rank look weak. This suggests 20.f4 Rf5 (20... Re6 21.Nc7 or 21.Qxf6) 21.Qxf6 Rxf6 22.Rd8 threatening 23.Nd6 winning the bishop.|
I also considered 20.Nc7 Rb8 21.Ne8:
A) 21... Qg5 22.f4 + -.
B) 21... Qe6(7) 22.Rd5
B.1) 22... Rxd5 (or 22... Re6) 23.Qg7#.
B.2) 22... f6 23.Nxf6+ Qxf6 24.Qxe5 + -.
B.3) 22... Nd7 23.f4 + -.
C) 21... Qh8 22.Re2
C.1) 22... f6 23.Nxf6+ as A.2.
C.2) 22... Rxe2 23.Nf6+ Qxf6 (23... Kg7 24.Ng4+ f6 (24... Kg8 25.Nh6#) 25.Qxf6+ Kg8 26.Nh6#) 24.Qxf6 + -.
C.3) 22... Nd7 23.Rae1 Rxe2 24.Qxh8+ Kxh8 25.Rxe2 Nb6 26.Nd6 Be6 27.b3 followed by Nxb7 with the better endgame.
I don't know. I probably would try 20.f4.
|Jun-20-09|| ||WhiteRook48: didn't get it. Tried 20 Re2 taking advantage of the pin|
|Jun-20-09|| ||Dr. J: <Confuse: The most difficult part ... was "Moving the knight to an edge square".>|
Please have a look at
W A Foldeak vs F Nagy, 1942
|Jun-20-09|| ||wals: Valery Neverov - Ahmed Ibrahim Hamed, 3rd Golden Cleopatra Closed 1999|
Analysis by Rybka 3 1-cpu: time 2 min 18 ply
1. (4.25): 20.Nc7 Rb8 21.f4 Rf5 22.Qxf6 Rxf6 23.Rd8 Rb6 24.Re1 Kg7 25.Ree8 Ne6 26.Rxc8 Rxc8 27.Rxc8 Rxb2 28.Nxe6+ fxe6 29.Rxc5 Kf6 30.Rc7 b6 31.Rxa7
2. (4.25): 20.f4 Rf5 21.Qxf6 Rxf6 22.Nc7 Rb8 23.Rd8 Rb6 24.Re1 Kg7 25.Ree8 Ne6 26.Rxc8 Rxc8 27.Rxc8 Rxb2 28.Nxe6+ fxe6 29.Rxc5 Kf6 30.Rc7 b6 31.Rxa7
|Jun-20-09|| ||al wazir: <Lambda, goodevans>: Our try 20. Nc7 Rb8 21. Ne8 fails because of 21...Qh8, although after 22. Rd8 black has practically no moves.|
|Jun-20-09|| ||TheBish: V Neverov vs A I Hamed, 1999|
White to play (20.?) "Very Difficult"
Candidate moves: Nc7, Rd6, f4
20. f4 Rf5 (forced, not 20...Re6? 21. Nc7) and Black will be able to extricate his rook via f6, either with or without the trade of queens, e.g. 21. Qe3 Qe6! 22. Qd3 Qe7 23. Nd6 Rf6, and White might have a slight advantage, but nothing close to a win.
20. Rd6 Qe7 accomplishes nothing.
20. Nc7! Rb8 21. Ne8! (much stronger than 21. Nd5) and White's indirect attack on g7 causes Black major problems:
A) 21...Qe7 22. f4! wins the exchange, since 22...Re1+ 23. Kf2! forces 23...Qxe8 24. Rxe1 and other rook moves allow 23. Qg7 mate.
B) 21...Qe6 is nearly identical to A)
C) 21...Qh8 (guarding both the rook and g7 square) 22. Rd8! and Black is practically paralyzed. The knight can't move because of Nf6+ winning the queen, the bishop on c8 is pinned, and if the rook on f6 moves, then Qxh8+ followed by Nd6, double attacking both the knight on f8 and the bishop on c8. Plus, White is threatening 23. Nd6 anyway, so Black will have to give up the exchange. Let's see...
Well, I found a winning line, but the game is simpler. For some reason, I didn't look for the same theme without the queens on, although in my line the queens will eventually come off anyway (in the 21...Qh8 line). The lesson here is, go for the simple win! The back rank rook (Rd8) is even stronger after the queens are off the board, and winning the exchange is much better with the queens off! (Less chance of going wrong, and usually the queens will need to be traded anyway to realize the material advantage.)
|Jun-20-09|| ||southeuro: Nc7 Rb8 Ne8 Qe7 Re2 gg|
|Jun-20-09|| ||CHESSTTCAMPS: <johnlspouge:> <I am self-critical, but not masochistic :)> |
Working out a fun, complex line is masochistic? :) Actually, I didn't even think of the game line until I saw the score. Looking to force an exchange of queens is rather unusual for a Chessgames puzzle!
<goodevans:> <<Lambda>, In the line we both chose it's essential to attack the pinned black rook with the R(d2) before attacking with the f-pawn. Otherwise black can wriggle out of it with ... Re1+.>
Why so? After 20.Nc7 Rb8 21.Ne8 Qe7 (for instance) 22.f4 Re1+ 23.Kf2! black must play Qxe8 and white wins an exchange with a dominating position.
<al wazir:> <<Lambda, goodevans>: Our try 20. Nc7 Rb8 21. Ne8 fails because of 21...Qh8, although after 22. Rd8 black has practically no moves>
After 22.Rd8, the threat of Nd6 wins an exchange after Re6 23.Nd6 (or exchange Qs first) Rxd6 24.Rxd6.
I wouldn't call that a failure - it should be an easy win, but not as strong as the game line.
|Jun-21-09|| ||remolino: The Bish:
I found this puzzle very istructive because after 20.Nc7 Rb8, 21.f4 Rf5, 22. Qxf6 Rxf6, 23. Rd8 Black is completely lost despite that material is even. And a key to that is that the queens were exchanged: Black's queen was one of the only Black's pieces active (plus the rook), while all white's pieces are active (even rook on a1 which will come into play). So the moral of the story: if the opponent only has one or two active pieces, see if you exchange them and overpower him with the rest of your much more active army
|Jun-21-09|| ||zenpharaohs: dzechiel: "One line I liked, but didn't seem to pan out was 20 Nc7 Rb8 21 Ne8. But after 21...Qe7 white doesn't seem to have anything."|
It does pan out, it's actually the line I considered the best. Although engine analysis favors the game line, the 20 Nc7 Rb8 21 Ne8 Qe7 line is fine for White - continuing (according to Deep Fritz 11):
21 Ne8 Qe7
22 Rd8 a6
23 Rad1 Qxe8
24 f4 Re2
25 Rxe8 Rxe8
The position looks very good for White to me, mainly because of significant advantages in space and development, coupled with weaknesses for Black's pawns. Deep Fritz 11 evaluated this at a bit more than +3 at 20 ply.
For a second machine opinion, I put checked the line with Rybka 3, obtaining:
21 Ne8 Qe7
22 Rd8 a6
23 Rad1 Qxe8
24 Rxe8 Rxe8
with a value here of +2.58 at 23 ply. Playing in a bit with Rybka 3 to see if the predictions of the engines for a bright future for White pan out:
25 g4 Bd7
26 Qa3 b5
27 cxb5 Bxb5
28 Qxc5 Rbc8
29 Qb4 Ne6
30 Bf1 Rc5
31 Bxb5 Rxb5
32 Qa4 Reb8
33 b3 a5
34 Qe4 Rc8
35 Rd7 Rb4
36 Qe1 Rb5
37 Qe3 Rbc5
38 Qf3 Rf8
39 Kg2 Rc2
40 a4 Rc5
41 Qf6 Rg5
42 Re7 Rc5
43 h4 Rc2
44 h5 gxh5
45 gxh5 Rc5
46 h6 Rg5+
47 Kf1 Rg6
48 Qh4 Rc8
49 Ra7 Rc1+
50 Ke2 Rc2+
This bit suggests that Black has nothing up his sleeve in this line other than delaying and harassing White.
51 ... Rc8
52 Rxa5 Rg1
53 Ke2 Re8
54 Kd2 Rd8+
55 Kc3 Rc1+
56 Kb2 Rcd1
Black has run out of ankles to bite for the moment. Although all that has occurred for quite a few moves is one pawn snatched and a lot of repositioning, Rybka 3 now values the position at over +5, which means that the game is pretty much resignable for Black, without some sort of miracle. However there is no quick end in site, and White trudges on:
57 Qf6 Rg1
58 Ra7 Rf8
I don't see how Black can stop the promotion threat.
59 ... Rg2
click for larger view
60 b4 Rg4
61 Qc3 Rg6
62 b5 Nd8
63 Rd7 Rxh6
64 a6 Rh5
65 Qg3 Kh8
No more Mr. Nice Guy. White uses the promotion threat to mobilize his pieces as well as paralyze Black's:
66 ... Ne6
67 a7 Kg8
68 b6 Ra5
69 Rd5 Ra4
Time is up for the Rook defending the promotion.
70 ... Rxa7
71 bxa7 h6
72 Qc6 Kh7
73 Rd7 Kg8
74 a8Q Mate in 12
So there was in fact no hope for Black. This line was calculated with very long searches for Black's moves, so there was probably no way out.
On the other hand, over the board, this line involved a lot of chances for White to misplay, or run out of time - Black can drag it out quite a bit.
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