< Earlier Kibitzing · PAGE 2 OF 2 ·
|Jul-16-11|| ||Creg: The position appears to be calling out for something to happen on the kingside. White has all his pieces aiming that way, while black has a queen and rook out of the equation.|
I first looked at taking on f6, but that lead nowhere. Then I realized that the knight at f6 couldn't move due to whites queen and bishop battery on the dark diagonal. That's when I thought about hitting f6 one more time with the other knight, but how?
That's when I looked for a clearance, or forcing move, such as 26. Bg6. The idea is simply to clear the h7 square for the knight at g5. The following exchanges lead to opening blacks position like a can opener, and that was good enough for me.
|Jul-16-11|| ||Rosbach: Black has no options to turn the game around after 26. Bg6. 26...Be6, 26...Rxe4 both lead to defeat. Black cannot escape white's tower.|
|Jul-16-11|| ||sevenseaman: <newzild><I got it, but my main line was different towards the end:>|
The game score, you and me have relied upon 26...fxg6, a non-forcing move.
You've hit a brilliant practical line. However the game turns White's way as soon as Black accepts the initial B sac.
Nd7 or Rxe6, the brunt of the idea is to obtain control of the long a1-h8 diagonal; thereafter its only hide and seek in an open field.
|Jul-16-11|| ||newshutz: I looked at Bg6, but did not see a good continuation for white after 26...Kg8|
|Jul-16-11|| ||kevin86: The object of all of this is to open the long diagonal for the bishop and queen.|
|Jul-16-11|| ||tbentley: Rybka discovered 26. Bg6 Kg8 27. Nxf7! Nxf7 28. Bxf7+ Kxf7 29. Ng5+|
A. 29...Kg6 30. g4 Kh6
A1. 31. Qc2 g6 32. Qf2 Rh8 33. Nf7+ Kg7 34. Nxh8 Kxh8 35. Qxh4+ Kg8 36. Bxf6 Bxf6 37. Qxf6
A2. 31. Rxe8 Bxe8 32. Qe1 Bh5 33. Qxh4 g6 34. Nf7+ Kg7 35. Nxd8 Qxd8 36. f5
A21. 36...Kg8 37. Bxh6 Qd2 38. gxh5
A22. 36...Qe7 37. fxg6 Kg8 38. Qxf6 Qxf6 39. Rxf6 Bxg6 40. Rxg6+
B. 29...Kg6 30. Qd3 Be6 31. Qg6
B1. 31...Qa7 32. Bxf6 Bxf6 33. Qh7+ Kf8 34. Rxe6 Rxe6 35. Nxe6+ Ke7 36. Nxg7 bxc5 37. Re1+ Kd8 38. Ne6+ Kc8 39. Qf5 Kb7 40. Qxf6
B2. 31...Be7 32. Nxe6+ Bxc5+ 33. Nxc5 Rxe1 34. Rxe1 Qf8 35. Ne6 Qe7 36. Qxe7+ Kxe7 37. gxh4
C. 29...Kf8 30. Qd3 Rxe1 31. Rxe1 Qa7 32. Qg6 Be8 33. Nh7+ Kg8 34. Nxf6+ Bxf6 35. Rxe8+ Rxe8 36. Qxe8+ Kh7 37. Qh5+ Kg8 38. Bxf6 gxf6 39. Qg6+ Kh8 40. Qxf6+ Kh7 41. Qxh4+
|Jul-16-11|| ||DrMAL: Looking back on where black went wrong, it seems he first took the wrong pawn (15...Nxe4 was correct) but did not get punished as much (either rook on e1 for move 18 was better). But then black executed his flank attack poorly (if that is what he was trying for, as he should have done) by not getting his queen active (e.g., 20...Qc8 followed by Nh5) and being inconsistent (21...b6 was a mistake no time for diversion).|
By move 26, white has several ways to win, 26.g4 may be even stronger but 26.Rd1 or 26.Qd3 or simply 26.Kg2 also work. The blunder 26...fxg6 lost much faster. Nice game for white!
|Jul-16-11|| ||David2009: D Gurevich vs C Kuperman, 1978 White 26?
Missed this by the proverbial country mile. I looked at 26.Bg6 fxg6 27 Qc4?? before deciding on 26. Qf3 intending to follow up with 27.Nxf6 or 27.Bxf6 depending on Black's response.
Here's the puzzle position: |
click for larger view
and here's a link to Crafty End Game Trainer:
http://www.chessvideos.tv/endgame-t... 26.Bg6 the EGT plays 26...Kg8 and like <sevenseaman> I couldn't find the win unaided. So I used electronic help (Fritz 12) to generate the following line which beats the EGT:
26... Kg8 27.Qd3 fxg6 28.Bxf6 Bf5 29.Qc4+ Be6 30.Nxe6 b5 31.Qc3 Rxe6 32.Bxg7 Nf7 33.f5 gxf5 34.Rxf5 Rg6 35.Be5 to reach
click for larger view
Here the EGT plays 35...Qb7!? and loses quickly to 36.Ref1 Qd7 37.Rxf7 Qxf7 38.Rxf7 Kxf7 39.Qd3 etc: a more spirited line is 35... Nxe5 36. Rxe5 Bc7 when Fritz 12 finds 37.Nf6+! Rxf6 38.Rg5+ Kf7 39.Qd3 etc.
I also tried my luck with 26.Qf3 and the magic of Fritz 12 again beats the EGT: 26.Qf3 Bxh3 27.Nxf6 (if 27.Bxf6 Bxf1) Bxf6 28.Bxf6 Bxf1 29.Be5! Rxe5 30.fxe5 Bb5 31.a4! (winning the Bishop) bxc5 32.axb5 cxb5 33.gxh4
click for larger view
and White's attack and extra piece easily outweigh Black's Pawns.
Question: Is it useful to present these winning lines or does this spoil things for other solvers? Should I just present the Crafty EGT link? - I have recorded, rather than discovered, these winning lines.
|Jul-16-11|| ||newton296: <tbentley: Rybka discovered 26. Bg6 Kg8 27. Nxf7! Nxf7 28. Bxf7+ Kxf7 29. Ng5+>|
to bad you don't have houdini!! because houdini finds a better line starting with Rd1!
check it out! houdini just barrels down the D file with the rooks and black falls apart! Dimitri Gurevich - Carlos Kuperman, URS 1978
click for larger view
Analysis by Houdini 1.5a x64:
1. (5.65): 26.Rd1 Qc7 27.Rd6 Be6 28.Rfd1 b5 29.Nxe6+
2. (2.93): 26.Bg6 Re6 27.Qd3 bxc5 28.Nxf6 Bxf6 29.Qxd7 Rxe1 30.Rxe1 Bxg5
|Jul-16-11|| ||DrMAL: <David2009: Should I just present the Crafty EGT link?> You did (again) but it is better than daily regurgitations of engine output (especially with diagrams) just saying. Maybe I am wrong but I thought the purpose of puzzle is to think and maybe kibitz on what we thought, not compare engines, cheers.|
|Jul-16-11|| ||Quentinc: <David2009>, despite the obnoxious reply you have received, I find it useful. Obviously the idea is to try to find the best lines for each side on our own, but here nobody came close. It's nice to be able to compare one's thought process with what is, unfortunately, the ultimate arbiter. For people who want to find the winning line on their own, they can just stop reading your post at the link.|
|Jul-16-11|| ||sevenseaman: <David2009> cheers for the exemplary hard work you must have had to put in to squeeze out a win against EGT. I liked going over it.|
As <DrMAL> points out, our primary aim in attempting POTDs is to exercise our own mind/cerebral muscle and find the best moves. Too bad if we do not always succeed. The more we try on our own the better. Failure at times teaches a lot.
If we kept that in mind then going for outside help is only a matter of having the time, resource and the inclination.
For instance I do not always wrestle with EGT; its time consuming. I do not have any other electronic analyzer. Basically its me and the puzzle.
So I will say your EGT link is a convenient option that I sometimes use depending upon availability of time.
It does widen one's horizon on defensive options. For instance today I should have thought of Black declining the initial B sac but didn't.
Gurevic got the same breaks. Its sort of part of the game - its never played perfectly as we all know.
|Jul-16-11|| ||thendcomes: <David2009>, for me, your posts are the best part of the daily puzzle. I enjoy the analysis. No one is forced to read it if they don't want to.|
|Jul-16-11|| ||DrMAL: Whatever, I don't care either, it was just a friggin friendly suggestion (horrors be LOL) and certainly NOT obnoxious (but calling it that most certainly IS obnoxious). |
In any event, the stuff on engines got me curious too, particularly since <newton296> quoted a line from Houdini that surprised me so I checked on that engine myself. I too learned something from an engine here, that 26.Rd1 was objectively best:
Houdini_15a_x64: 21/77 1:30:00 19,716,014,893
+4.21 26.Rd1 Bxh3 27.Nxh3 b5 28.Nd6 Re2 29.Rfe1
+3.35 26.Bg6 Re6 27.Qd3 bxc5 28.Nxf6 Bxf6 29.Qxd7
+3.05 26.Nd6 Rxe1 27.Rxe1 a4 28.Ndxf7 Nxf7 29.Nxf7
+2.96 26.Qf3 Nxe4 27.Bxe4 bxc5 28.Rd1 Qc8 29.Rd6
+2.68 26.Kg2 Ra7 27.g4 b5 28.Qd4 Be7 29.Nd6
+2.61 26.g4 bxc5 27.Nxc5 Qa7 28.Rxe8+ Bxe8 29.Nge4
These lines are different from short term computation, cheers.
|Jul-16-11|| ||agb2002: The material is even.
Black threatens ... hxg3 worsening White's pawn structure.
The knight on f6 prevents Qxg7. This suggests 26.Bg6 threatening 27.Nxf6 and 27.Nh7+:
A) 26... fxg6 27.Nh7+
A.1) 27... Nxh7 28.Qxg7#.
A.2) 27... Kg8 28.Nhxf6+
A.2.a) 28... gxf6 29.Nxf6+ Bxf6 30.Qxf6 Nf5 31.Qxg6+ Kf8 32.Qf6+ Kg8 33.Qh8+ Kf7 34.Qh7+ Kf8 35.Qxd7 + - [B+2P vs N].
A.2.b) 28... Bxf6 29.Nxf6+ transposes to A.2.b.
A.2.c) 28... Kh8 29.Nxd7 + -.
A.3) 27... Kf7 28.Qc4+ B(R)e6 29.Neg5+ Kg8 30.Rxe6 R(B)xe6 31.Qxe6+ Kh8 32.Nf8 followed by Nxg6#.
A.4) 27... Ke7 28.Nxf6+ is crushing.
B) 26... Bxh3 27.Nh7+ (27.Nxh3 fxg6)
B.1) 27... Nxh7 28.Qxg7+ Ke7 29.Nd6+ Be6 30.Rxe6+ Kxe6 (30... Kd7 31.Rxe8 + -) 31.Bf5+ Nxf5 (31... Kd5 32.Qd4#) 32.Qxf7#.
B.2) 27... Kg8 28.Nexf6+ Bxf6 (28... gxf6 29.Rxe8+) 29.Nxf6+ gxf6 30.Qxf6 wins.
B.3) 27... Ke7 28.Nexf6+ Be6 29.Nxe8 + -.
C) 26... Bf5 27.Nh7+ looks similar to B.
|Jul-16-11|| ||morfishine: MY DAY: As I have the weekend off and need some relaxation, I decided to try a different approach to the POTD, and its this: I would set-up the position and view for about 3-minutes. (Not to look at variations but to memorize the position.) After that, I would let my sub-conscious provide the solution. I would block out all thoughts of the puzzle and go about my errands: purchasing foodstuffs, gassing-up the autos, make a stop at the used bookstore and re-stocking the beer supplies. All the while, my sub-conscious should, theoretically, be solving the puzzle. |
NOTE: Its important to not focus on anything that requires mental exertion. This could distract from the sub-conscious. The idea comes from the old advice: "You got a problem? Sleep on it: in the morning, you'll have your answer"...or something like that.
In any case, when I returned home and entered the study (with the position still set-up), a light-bulb went off as I realized I'd successfully blocked out all thought of the POTD. Now was the time for the sub-conscious to reveal the solution!
Alas, nothing. Feeling betrayed, I spent a few moments looking at <26.g4> and <26.B6> and finally decided on one move: <26.g4>
Every now and then, even the sub-conscious needs a weekend off.
|Jul-16-11|| ||wals: Rybka 4 x 64 : d 19 : 2hrs 10 min :
1. (3.15): 26.Rd1 Bxh3 27.Nxh3 bxc5 28.gxh4 c4 29.bxc4 a4 30.Nhg5 Qb3 31.Rd6 Qxc3 32.Bxc3 Nxh7 33.Rxh6 gxh6 34.Nxh7+ Ke7 35.Re1 Rg8+ 36.Kh2 Kd7 37.Nhf6+ Bxf6 38.Nxf6+ Kd6 39.Nxg8 Rxg8 40.Re5 Kd7 41.Rh5
2. (2.77): 26.Bg6 Kg8 27.Qc4 Nd5 28.Qd4 Bf6 29.Nxf6+ gxf6 30.Qd3 Kf8 31.Be4 Rxe4 32.Nxe4 Bf5 33.g4 Bxe4 34.Qxe4 bxc5 35.Rf3 Ng8 36.g5 Qb6 37.Qh7 c4+ 38.Kh1 c5 39.Qe4 Rd8 40.Qxc4
3. (2.32): 26.g4 bxc5 27.Nxc5 Qa7 28.Rxe8+ Kxe8 29.Qe3+ Be7 30.Bd4 Qc7 31.Bxf6 gxf6 32.Nge4 Kf8 33.Qd4 Qa7 34.Nxd7+ Kg7 35.Qxa7 Rxa7 36.Ndxf6 Bxf6 37.Nxf6 Kxf6 38.Be4 Ng8 39.Bxc6 Rc7 40.Be4 Kg7 41.g5
|Jul-16-11|| ||BOSTER: <newzlid> <Interesting to see that some strong regulars did not get it>.
This is because of their absence.|
|Jul-16-11|| ||WhiteRook48: no!! I tried 26 Bg8 instead|
|Jul-16-11|| ||tacticalmonster: 1) White has strong battery along the a1-h8 diagonal|
2) Both a8 rook and h6 knight is offside
3) White should put more pressure on f6 knight which defends g7
4) White needs open files for his rook
candidate: 26 g4
White has the idea of g4, f5, Ne6+, fxe6 and g5 with the idea of pressuring the f6 knight
|Jul-16-11|| ||tacticalmonster: Not even close. I even looked at for over half an hour! I was completely confused by today puzzle.|
|Jul-16-11|| ||rilkefan: Didn't see 31.Nd7; otherwise feel pretty good about today. Though if I hadn't known it was a puzzle I might not have instantly looked at Bg6/Nh7+.|
|Jul-17-11|| ||sevenseaman: <morf> your last post set me thinking. How do we solve puzzles or what particular approach is best. Clearly it is beyond generalization as its somewhat
a matter of individual style. Still!
1. Having had a look and not having got the solution I cannot really shut it out of my mind.
2. Being a Houdini is well nigh impracticable; at times one needs a bit of luck.
3. If I do not get it in 4-5 minutes, there's little chance that inspiration will hit me later.
4. Electronic aids prior to the solution are addictive walking sticks that sap self-belief.
5. A measure of clarity in all aspects of life is a thinking man's basic need. He abhors living with unsolved riddles.
6. Mystery engenders fear and no one ever chooses to be afraid. Hence very clever of <CG> to provide the solution in all due anonymity on the next page.
So whats the best approach? I'd say 'The Sun rises every day and we just face it, with grit, resolve and enjoyment.'
|Jul-17-11|| ||DrMAL: <sevenseaman> Any high level player being honest will tell you: most of the time it is intuition it's impractical to calculate everything out. This position is a great example of that, there are at least half a dozen winning moves for white. It is not so much a matter of finding the optimal move but instead having a move that feels right, then making it with confidence and going from there. Hope that helps, cheers!|
|Jul-17-11|| ||morfishine: <sevenseaman> As we are drifting off-topic, I left a response to your 6-points at my forum. I enjoy conversing with you. Best, Morf|
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