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< Earlier Kibitzing · PAGE 3 OF 4 ·
Later Kibitzing> |
| Feb-06-10 | | cyclon: Okay, it seems like <patzer2:> "chip-chaps" has answered into my inquiry. Though computer-line would be very difficult to find over the board! |
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| Feb-06-10 | | jackpawn: Actually I thought it was relatively easy for a Saturday. Did I see it all the way up to the 18th move? No, but it's the type of sac you can make without actually seeing all the way to the end - you just know there should be a killer tactical shot at some point. |
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Feb-06-10
 | | An Englishman: Good Afternoon: So 18.Rh3 is the killer. That is one subtle but nasty shot. |
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| Feb-06-10 | | Marmot PFL: Definitely Exchange Grunfeld with early h4 where black has delayed c5. Usually this leads to kingside assaults. Here 15 d5 is tempting, hoping for 15...Bxc3+? 16 Bd2 with attack, but simply 15...ed5 is OK. There are knight sacs followed by Qg4 with strong threats of Bxe6+ or Qxg6 and Rh3 or Bh6. Not 15 Nxg6 Nxd4! but 15 Nxe6 is looking good. One trick is 15 ef 16 Qg4 Kf7 17 Rh7 Rh8? 18 Bxe6+ but even 17...Rg8 18 Bh6 and Qf4 seems to win. Several other defences are also met by Qh7+, Rh3 or Bh6 in various sequences. At this point unless I could see a refutation I would play this sacrifice on intuition as my experience defending such positions tells me black is in serious trouble. |
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Feb-06-10
 | | Domdaniel: A couple of people have pointed out that White has other ways to win besides 18.Rh3 (in the main game continuation). This is true, but with some reservations. The Rook lift will almost certainly be needed on a later move anyway. For example, 18.cxd4 Qxd4 and now White's best is 19.Rh3. Amusingly, 18.Rh4 - with most of the same ideas - also seems to win. I just find it hard to imagine anyone actually playing it. Overall, in an OTB situation rather than a puzzle, I still think that the 15...Ne5 16.Nxd8 Nd3+ is Black's best practical chance. White can win, but only by finding a Queen sac and some other tricky moves. |
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| Feb-06-10 | | johnlspouge: Saturday (Very Difficult)
P Cramling vs S Kindermann, 1991 (15.?) White to play and win.
Material: Even. The Black Kg8 has 1 legal move, f8. The White Rh1 has an open file, direct to Kg8, suggesting a heavy piece battery. The Black Pg6 prevents Qd1-h5, but the P-chain protecting Kg8 is under fire from Bb3 and Nf4, suggesting a sacrifice to open Kg8 and to take advantage of the superior White mobility. Note: the White Qd1 can reload Bb3; and Bc1-a3 might be useful in a K-side attack. The White Ke1 is secured from check. Candidates (15.): Nxg6, Nxe6
15.Nxe6 (threatening 16.Nxd8, winning the exchange)
(1) Black can decline the sacrifice:
15…Re8 16.Ng5 (threatening 17.Bxf7+)
The threats on Pf7 give White time to stabilize the center and keep the P. (2) Black can accept the sacrifice:
15…fxe6 16.Qg4 (threatening 17.Bxe6+, forking Kg8 and Qd7) 16…Re8 [better than Bc8, undeveloping a piece]
17.Qxg6
(threatening to overburden with 18.Rh7, 18.Bh6, or 18.Qh7+) (1) 17…Nd8 18.Rh7 (threatening 19.Rxg7+ Qxg7 20.Qxe8+) 18…Kf8 19.Bh6 Re7 20.Bxg7 Rxg7 21.Rh8+ Ke7 [Rg8 22.Rxg8#] 22.Qxg7+ 23.Qxd7+ 24.Rxa8 leaves White with 2R for N. (2) 17…Qf7 18.Rh8+ Kxh8 19.Qxf7 leaves White with Q+2P for R+N. (3) 17…Bc8 18.Rh7 (threatening 19.Rxg7+ Qxg7 20.Qxe8+) 18…Re7 19.Bh6
The Bg7 can no longer be defended, so Black loses material. I considered Black counter-attacking at d4, but dismissed it as futile. |
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Feb-06-10
 | | Jimfromprovidence: After 15...Ne5 16.Nxd8 Nd3+ 17 Kd2...
<DomDaniel> < Simply 17...Rxd8 is better. Black has now sacrificed the exchange - but threatens to win it back with ...Nxf2, and has great compensation. The White King interferes with the Bc1 and is vulnerable to blows like ...c5, and the threat to f7 is largely neutralized.> In this line here is the position assuming white follows 17...Rxd8 with 18 Qf3. Now comes 18...c5. 
click for larger viewBlack threatens both 19..cxd4 or 19...c4. Of course, white cannot play 19 cxd5?? because of 19...Ne5+, winning the queen. Yes, black is down material, but what a position. |
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| Feb-06-10 | | johnlspouge: < <Once> wrote: Well, I had the same basic idea, but I sacked the knight for the other pawn... > Most tactical strokes have a "conjugate", i.e., the symmetry of the pieces' movements often creates two possible strokes. Usually, one of the two conjugates is clearly superior, so it pays to recognize the phenomenon explicitly, to look for conjugates and to compare them explicitly. Here, acceptance of either 15.Nxe6 fxe6 or 15.Nxg6 fxg6 leads to the same position, but the sacrifice 15.Nxe6 is more forcing than 15.Nxg6, essentially brooking no refusal. |
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Feb-06-10
| | Jimfromprovidence: After 15.Nxe6 Ne5 16.Nxd8 Nd3+ 17.Qxd3 Bxd3 18.Nxf7 Kf8 19.Ba3+, what if 19...Ke8 20.0-0-0 Be2 instead? I'm stuck.
click for larger view |
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| Feb-06-10 | | Quentinc: Given the complications and uncertainty of 15...Ne5 16.Nxd8, what about the "cowardly" (i.e., what I probably would have played OTB) 16.Nf4 instead? If 16...g5 17.Qh5, and White looks at least a little better in the lines I've played through. |
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| Feb-06-10 | | patzer2: <JimjfromProvidence> <I'm stuck> Analysis by Fritz 10 @ 19 depth, 2-cpu:
1.  (4.95): 21.Ne5 Bxe5 22.dxe5 Qg7 23.Rd2 Bg4 24.f4 b5 25.Rh4 Bc8 26.Bd5 g5 27.Rh5 gxf4 28.Bxa8 Kf7 29.Rd8 Be6 30.Bd5 Kg6 2. (4.79): 21.Rd2 Bh5 22.f3 Qc6 23.Kb2 Rd8 24.Nxd8 Kxd8 25.e5 Kc8 26.Rdd1 a5 27.g4 Qxf3 28.gxh5 gxh5 29.Be6+ 3. (1.57): 21.Rde1 Bc4 22.Ne5 Bxe5 23.dxe5 Qc6 24.Rh8+ Kd7 25.Rd1+ Ke6 26.Rh7 Re8 27.Bc2 Kxe5 28.Rdd7 Bg8 29.Rxc7 |
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| Feb-06-10 | | patzer2: <Quentinc> After 16...Ne5 16. Nf4?! Qc6 17. Qc2  White no longer has a clear forced win (i.e. 16. Nxd8 wins with strong follow-up). |
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| Feb-06-10 | | LoveThatJoker: <Jimfromprovidence: After 15...Ne5 16.Nxd8 Nd3+ 17 Kd2... <DomDaniel> < Simply 17...Rxd8 is better. Black has now sacrificed the exchange - but threatens to win it back with ...Nxf2, and has great compensation. The White King interferes with the Bc1 and is vulnerable to blows like ...c5, and the threat to f7 is largely neutralized.> In this line here is the position assuming white follows 17...Rxd8 with 18 Qf3. Now comes 18...c5. Black threatens both 19..cxd4 or 19...c4. Of course, white cannot play 19 cxd5?? because of 19...Ne5+, winning the queen. Yes, black is down material, but what a position.> Interesting line here that DomDaniel presented based on Jimfromprovidence's original suggestion of 15. Nxe6 Ne5. I'm actually in agreement that after 15. Nxe6 Ne5 16. Nxd8 Nd3+ 17. Kd2 Rxd8 18. Qf3 is a decent choice. If now 18...c5 19. d5 begins consolidating the material advantage. LTJ |
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| Feb-06-10 | | cyclon: <Jimfromprovidence: In this line here is the position assuming white follows 17...Rxd8 with 18 Qf3. Now comes 18...c5.> It's really true that White is encountering problems here in this variation, no doubt. However, after 18. -c5, I'd play 19.Bd5 (if -cxd4 20.cxd4 Bxd4 21.Rb1 - but there's probably something else also). |
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| Feb-06-10 | | cyclon: <LoveThatJoker: If now 18...c5 19. d5 begins consolidating the material advantage.> Perhaps 19.d5 is Whites best move here, I don't know for sure. I find this position (after 18. -c5) very difficult to estimate in a satisfying manner. |
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| Feb-06-10 | | LoveThatJoker: <cyclon: <Jimfromprovidence: In this line here is the position assuming white follows 17...Rxd8 with 18 Qf3. Now comes 18...c5.> It's really true that White is encountering problems here in this variation, no doubt. However, after 18. -c5, I'd play 19.Bd5 (if -cxd4 20.cxd4 Bxd4 21.Rb1 - but there's probably something else also).>
Hey cyclon. White is not encountering any problems at all in this line. Of course, White has a slightly awkwardly placed K and an undeveloped Q-side. However, the dark-squared Bishop does yet have an outlet at a3 (if needed) and White is up 3 in the force count. The onus now is on Black to prove that he has compensation for being down 3 in the force count and after 18...c5 19. d5, I don't think he does. I would gladly take White in such a position.
LTJ |
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| Feb-06-10 | | cyclon: cyclon: <LoveThatJoker:> To demonstrating what I mean in the sense that things may not (just maybe not) be so clear YET (even at the same time admitting the probable plausibility -in the good sense- of 19.d5), is the idea for Black to play 19. -Qb5, intending -Qa5 with a square c3 in sight. For example; (19. -Qb5 ) 20.d6 Ne5/20.Kc2? c4/20.c4 Qb4+ 21.Kxd3 Qc3+ 22.Ke2 Qxa1 23.Bg5 Qb2+, White still has `proving`. Maybe you have some idea? Anyway, thank you from your post! |
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| Feb-06-10 | | SamAtoms1980: I went in with the wrong piece with 15 Bxe6 fxe6 16 Nxg6, which gets completely smoked by 16 ... Nxd4. |
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| Feb-06-10 | | gofer: I could write for ages on this one... ...but the following is enough... 15 Nxe6 fxe6
16 Qg4 Bc8 (better than Re8 and Qe8/Qf7/Kf7 all lose quickly)
17 Bg5 ...
now this is debatable, Ba3 is also good, but I prefer Bg5 17 ... Ne7 (trying to stop Qxg6)
18 Rh3 Kf7 (trying to get to saftey)
19 Rf3+ Ke8
20 Qf4 winning as black must give up material...
There are probably thousands of variations and this is just one, but its one I kind of like... Time to check... |
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Feb-06-10
| | Jimfromprovidence: After 15.Nxe6 Ne5 16.Nxd8 Nd3+ 17.Qxd3 Bxd3 18.Nxf7 Kf8 19.Ba3+, what if 19...Ke8 20.0-0-0 Be2 instead? <Patzer2> <*Analysis by Fritz 10 @ 19 depth, 2-cpu: 1. (4.95): 21.Ne5 Bxe5 22.dxe5 Qg7 23.Rd2 Bg4 24.f4 b5 25.Rh4 Bc8 26.Bd5 g5 27.Rh5 gxf4 28.Bxa8 Kf7 29.Rd8 Be6 30.Bd5 Kg6> Thanks for the assist. Your lines show that the queenside castling on move 20 for white is quite decisive. |
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| Feb-06-10 | | remolino: I would go for 15.Nxg6
A. 15.Nxg6 fxg6, 16. Qg4 Nxd4, (16...Re8, 17. Qxg6) 17. cxd4 B. 15. Nxg6 Nxd4, 16. Qh5
Time to check. |
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| Feb-06-10 | | remolino: OK, 15. Nxe6 seems more decisive. will check whether Nxg6 works too on the kiblitzers posts. |
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| Feb-06-10 | | Skylark: <David2009> - check my analysis above - I came to the same conclusion of choosing Nh5, but rather than a3 the queen should take straight away on h5 and follow up with Bh6. It took a while for the engine to turn the position around to a slight plus for white though (rybka 2.2n2) rather than the game continuation which is outright winning. |
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| Feb-06-10 | | DarthStapler: I at least considered the first move |
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| Feb-06-10 | | LoveThatJoker: <cyclon: <LoveThatJoker:> To demonstrating what I mean in the sense that things may not (just maybe not) be so clear YET (even at the same time admitting the probable plausibility -in the good sense- of 19.d5), is the idea for Black to play 19. -Qb5, intending -Qa5 with a square c3 in sight. For example; (19. -Qb5 ) 20.d6 Ne5/20.Kc2? c4/20.c4 Qb4+ 21.Kxd3 Qc3+ 22.Ke2 Qxa1 23.Bg5 Qb2+, White still has `proving`. Maybe you have some idea? Anyway, thank you from your post!> Hey cyclon. Thanks for your note, man.
Trust me! I spent a lot of time trying to find a direct refutation to 19...Qb5 and came up with a lot of lines. As you know, I do these blindfold so as to improve my OTB tactical vision. That's why I needed a little time in replying to you. Here are some that still maintain a decent advantage for White a) 20. Rb1 c4 21. Bc2 Qa5 22. Bb2 Qxa2 23.
b) 20. Rb1 Bxc3+ 21. Kxc3 Qb4+ 22. Kc2 c4 and now Fritz 12 found 23. Qh3! with a huge advantage to White. That being said after 19...Qb4 20. Rb1, Fritz 12 says that Black has an immediate draw by 20...Ne5 21. Qe3 Ng4 22. Qf3 as White must protect against the mate threat on e2. Also, I had looked at the line that Fritz 12 saw immediately which is 20. c4 Qb4 21. Kxd3 Qc3+ (21...Bxa1? 22. Bd2) 22. Ke2 Qxa1 but didn't like it because I thought that White had failed to trade material down (so as to have a big advantage with an active K and passed pawn.) However, Fritz 12 found this continuation,
23. Qd3 Bb2 24. Qd2 Bxc1 25. Qxc1 Qe5 26. Qe3 Re8 27. f3 f5 28. Qh6 Kf7 29. Qg5 Kg7 30. Rh6 fxe4 31. Qxg6+ 1.63/21 Admittedly, 17...Rxd8 provides a really good defensive try for Black, however, I am glad that I found all these lines blindfold and do not instantly need to run to Fritz or to play these moves out by hand so as to formulate a competent opinion. This isn't necessarily directed at you Cyclon, as I do not know how you approach the analysis of positions. However, it is directed at those who like to hide their small capacity for hard work behind 1's and 0's. :D LTJ |
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Later Kibitzing> |
Kibitzing
sac: 15.Nxe6