< Earlier Kibitzing · PAGE 2 OF 2 ·
|Sep-28-08|| ||noTALent: Or maybe it was a sunday puzzle because the need was to avoid the temptation of trying dzechiel:'s 26...Rxe1+ 27 Rxe1 Ng3+ |
I either couldn't work it out far enough or didn't think it was very solid, and so I was able to find the Bxg2 much quicker.
|Sep-28-08|| ||stukkenjager: here's a sample line for 28.Kh1:
26...Bxg2+ 27.Kxg2 Nf4+ 28.Kh1 Qb7+ 29.f3 Bg3 30.Ne5 Rxe5 31.Rxe5 d3 32.Qd1 Qxd7 33.Qf1 Ra5 34.b7 Rb5 35.Rxc5 Rxb7 36.Rcc1 score -5.55
|Sep-28-08|| ||whiteshark: I thought it was <26...Ng3+> with <27.Kxh2 Nf1+ 28.Kg1 Qh2+ 29.Kxf1 Qh1#>.|
|Sep-28-08|| ||Once: <whiteshark> 26. ...Ng3+ would be a good "shower of gold coins" move, but 27. fg rather spoils the party, eg|
26... Ng3+ 27. fxg3 Rxe1+ 28. Rxe1 Qxg3 29. gxf3 Qxe1+ 30. Kxh2
|Sep-28-08|| ||Woody Wood Pusher: 28. Kh1 line is so much more complicated than 28.Kxh2 IMO...|
|Sep-28-08|| ||zooter: I too saw 26...Bxg2+ 27.Kxg2 Nf4+ but then there were too many options for white and I didn't consider this line further|
|Sep-28-08|| ||whiteshark: Thanks <Once>!! I should have drunk my sunday morning cup of coffee before flippantly posting a sunday puzzle solution. :D|
|Sep-28-08|| ||chrisowen: Nice combination. I didnt elicit the final line but thought it was a pretty clean finish. 24 Bf5 bloes a gasket and Zybnek soon takes over by Bxf3. Ra4 around move 35 is ok e.g. 36. Nd6 Re6 Ra1 Rb4 Ra8 Kh7 and black changes gear. Looking forward to next month's scrabble.|
|Sep-28-08|| ||JG27Pyth: An Englishman: <I got it! I can't believe this, but I got it! Not the entire twelve move combination, of course <(Hracek probably didn't, either)>>|
Bravo -- I sure didn't get it... not even close. (Got Bxg2, let's just leave it there...;)
But about the "didn't see it all comment" ... there's no way to know without asking him, but I think Hracek _did_ see this deeply. GMs do, that's why they're GMs. They can calculate deep variations in their heads -- powerful memory and calculative gifts + the board sense that keeps them from wasting mental bandwidth on second guessing themselves and chasing down lines that offer nothing -- makes it possible.
I'm not speaking from experience obviously... but I've been reading "Excelling at Chess Calculation," by Jacob Aagaard and reviewing his material it's clear that master level chess involves calculating at this kind of depth... not every move certainly...but the book is about
A)recognizing when it's time to calculate deep variation and B)developing the mental chops to do it.
Everybody in NBA can dunk.
|Sep-28-08|| ||johnlspouge: Sunday (Insane): I Sokolov vs Hracek, 1996 (26…?)|
Black to play and win.
Material: Up a P. The White Kh1 is stalemated. The position is wildly imbalanced, featuring White's huge spatial advantage on the Q-side and Black's aggressive piece placement on the K-side. The Black Ra8 and Re8 both have open files, Qb8 and Bh2 form a battery on the b8-h2 diagonal, Bf3 is on the same diagonal as Pg2 and Kh1, and Nh4 can move to check Kh1 or threaten light squares on the White K position. All Black pieces are active. The position is tense, however, because the White Bd7 threatens Re8, Pg2 threatens Bf3, and the protection of Ba2 is tenuous. The threatened loss of material requires a substantial counter-threat. The White capture Bxe8 self-blocks the invasion point e8, costing considerable momentum. Overall, the positional features favor Black, but the tactical features predominate presently.
Candidates (26…): Bxg2+, Ng3+, Rxe1+, Qb7, Qf4
26…Qb7 (threatening 27…Qxd7)
Toga gives the refutation 27.Bxe8, and the basic idea is that 26...Qb7 is not forcing enough to handle all the White threats.
Like many, I went as far as 27...Nf4+, but decided Black had burned too much material to force a win.
One could summarize the position as follows. If you do not select a check or an extreme threat as the candidate, 26...Rxe1+ is mandatory to avoid losing material to Bxe8. The candidate 26...Rxe1+ drains the tension from the position, however, and it surrenders the e-file, a resource critical to both sides (which is why I rejected it). After you discard the three candidate checks, the remaining candidates are not forcing enough to blunt the multiple captures available to White.
|Sep-28-08|| ||Jimfromprovidence: I tried both 29 f4 and Ne5 as possible defenses for white. |
They both look like credible moves and may be better thant the text 29 Kg1, but ultimately they did not work.
|Sep-28-08|| ||A.G. Argent: <Once> So you were closer than you realised but now you've blown your cover. Your insecurities and fears, "Fischer"-esque or otherwise, are known to the entire chess e-cosmos. You've admitted to too much. And that creepy music thing must be awful. But never give in. Trust your instincts. Always keep going and remember the immortal words of the great and still mortal Yogi Berra; "When you come to a fork in the road, take it."|
|Sep-28-08|| ||fritochip: My best guess was Bxg2 followed by the Nf4 and the discovered check. But I couldn't figure out what to do with the Knight. I was so bent on a forced checkmate or snapping up the queen, that I missed the pressure the Knight could put on the rook on e1. |
I guess the moral of the story today is that if any of us play Mr. Hracek, bet on Mr. Hracek.
|Sep-28-08|| ||Bobsterman3000: I wonder how well the "average" 2700+ Super-GM would fare in finding the right moves to this puzzle...|
|Sep-28-08|| ||patzer2: For today's difficult Sunday puzzle, Black wins with a demolition of pawn structure to undermine the weak King position with 26. Bxg2+!!|
Here's a breakout:
Though not as clearly decisive, Black can secure a small advantage with some winning chances after 26...Rxe1+ 27. Rxe1 Nf6 28. gxf3 Nxd7 29. b7 Qxb7 30. Kxh2 Qxf3 .
<27. Kxg2 Nf4+ 28. Kxh2>
If 28. Kf1, then it's mate after 28...Qb7 29. Rxe8+ Rxe8 30. f3 Qxf3+ 31. Qf2 Qh1+ 32. Qg1 Qxg1#.
If 28. Kh1, then Black is on top after 28...Qb7+ 29. f3 Bg3! 30. Ne5 Rxe5 31. Rxe5 d3 32. Qd1 Qxd7 33. Qf1 d2 34. Rd1 Ra2 35. Bc3 Nd5 36. Rxd5 Qxd5 37. Qe2 Bf4 38. Qg2 f6 39. Qg4 Ra4 40. Kg2 Qd3 .
If 28. Kf3, then it's mate-in-three with 28...Qb7+ 29. Kg4 Qg2+ 30. Kh4 Qg5#
<28... Nd3+ 29. Kg1>
If 29. Ne5, then Black is winning after 29...Nxe1 30. Rxe1 Rxe5 31. Rxe5 Qxe5+ 32. Kg1 Rb8 .
If 29. Re5, then Black wins with 29...Nxe5 30. Nxe5 Rxe5 31. Kg1 Qb7 32. f4 Re3 .
<29... Nxe1 30. Qf5 Qb7 31. f3 Nxf3+ 32. Kf2>
If 32. Kf1, then Black has a mate in the works after 32...Nh4! 33. Qg4 Qh1+ 34. Qg1 Qe4! 35. Bxe8 Rxe8 .
<32... Nh4 33. Qg4 f5 34. Qxh4 Qxd7 35. Qf4 Qe6 36. Nd2 Qe3+ 0-1>
|Sep-28-08|| ||johnlspouge: <<dzechiel> wrote: [snip] I considered 26...Bxg2+ followed by the knight check, but the rest of the play was 'way out of my league, and I discarded it.>|
Hi, <dzechiel>. I do not share your modesty about Sunday puzzles, although (A) I would be better off if I did; and (B) you probably would be better off if you did not.
In any case, here is a point of interest.
Take the White Bb2 and put it on d2.
click for larger view
Now, 26...Rxe1+ is the best move (about +0.5 P for White), and 26...Bxg2+ goes down in hideous flames (about +3.5 P for White).
Given that you did not see the combination sufficiently to justify the move 26...Bxg2+, <dzechiel>, you would probably give 26...Rxe1+ as the candidate for both positions. If you did, you would not be playing a losing move in either.
My point, of course, is that unless today's puzzle candidate is justified with enough precision to differentiate the puzzle position from the "decoy" above, one will pay for "brilliant" wins over the board with compensating routine losses.
CG will not implement <MAJ>'s suggestion about a decoy position for the puzzle, but I will fill the void ;>)
|Sep-28-08|| ||johnlspouge: <<JG27Pyth> wrote: [snip] Everybody in NBA can dunk.>|
Hi, <JG27Pyth>. Although I have consistently speculated positively on this point, I appreciate knowing for sure...
|Sep-28-08|| ||Patriot: My first thoughts were "What does white threaten?" How about Rxe8+ and gxf3? Being aware of those threats I would consider Rxe1+, but first I would start looking at what black can do to white. 29...Bxg2+ 30.Kxg2 Nf4+ 31.Kxh2 walks into a discovery, so Nd3+ and Ne2+ looked interesting. But what if white avoids the discovered check and moves Kh1 or Kf1 or Kf3? Now black is down in material and Rxe8+ is still threatened! There was much more in this position than I wanted to analyze, but obviously those details MUST be worked out before deciding Bxg2+.|
|Sep-28-08|| ||Patriot: Sorry...Make that move 26 in my previous post.|
|Sep-28-08|| ||patzer2: <johnlspouge> <Now, 26...Rxe1+ is the best move (about +0.5 P for White)> Are you sure? My computer shows it coming out even on a quick scan, but as I slide forward and play it out Black has good winning chances. OTB my playing experience tells me it's a hard position (extra pawn and two connected passers versus a piece) for White to hold.|
|Sep-28-08|| ||Bobsterman3000: <Everybody in NBA can dunk>|
Not necessarily true. There's been a host of very small NBA guards that either couldn't dunk or could never hope to dunk in a game.
Mugsy Bogues and Earl Boykin are two examples.
|Sep-28-08|| ||johnlspouge: <<patzer2> wrote: <johnlspouge> <Now, 26...Rxe1+ is the best move (about +0.5 P for White)> Are you sure?>|
I am old enough to be sure of nothing, and I suspect you are too :)
As I now slide forward, 26...Rxe1 seems to rise to about +1.0 P for White, so my original evaluation probably underestimated White's chances.
My point was more, however, that in the absence of a clear tactical kill, the move 26...Rxe1+ is best, certainly much better than 26...Bxg2. I do not doubt your positional judgment at all, however: the move 26...Rxe1+ probably does lose even in the altered diagram.
|Sep-29-08|| ||MostlyAverageJoe: <johnlspouge: As I now slide forward, 26...Rxe1 seems to rise to about +1.0 P for White, so my original evaluation probably underestimated White's chances>|
Indeed. For the modified position (<Take the White Bb2 and put it on d2>), at 21 plies, Hiarcs and Shredder both show evaluations close to 2.0, rising higher after moderate sliding forward.
So it seems that moving the bishop changes the winning side from black to white.
|Sep-29-08|| ||newzild: Too hard for me, dammit.
6/7 this week.
|Sep-29-08|| ||kevin86: The final position was a case where a fork leads to an exchange and a similar fork.|
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