< Earlier Kibitzing · PAGE 3 OF 3 ·
|Jun-28-08|| ||Jimfromprovidence: So, what should black have done differently on move 21? Maybe 21…Re8 would have helped.|
click for larger view
This continuation gives the king another escape square, attacks white’s passed pawn and likely only costs black his c pawn,
|Jun-28-08|| ||vanytchouck: O.K. :
Like everyone, i can't help thinking about 22. Nf6 + threatening Qxh7 #.
So i see gxf6 or Nxf6 and i feel that white musn't take back on f6 using that the black pawn on f6 is preventing the black Queen and the Nd5 from helping the (almost) lone king.
As the Rd1 won't help much (the threat Rxd7 is not efficient because of Qc6 and maybe Nf6), while Rxd1 + is annoying, i started to consider the exchange Rxd5 (getting rid of a denfender).
22. Bf6 seems too slow (to be checked).
So my candidates are : Nf6+ and Rxd5.
Let's try :
a) 22. Rxd5 Rxd5 (i think that the Qc6 must stay on the 6th rank to protect the f6 square, and the R in d5 is attacking the e5 pawn).
23. Nf6 +
* 23...Qxf6 24. Bxf6 gxf6 25. Qg4 + Kh8 26.exf6 with material advance for white (Q+P vs R+B).
* But 23...+ gxf6 24. Bxf6 Nxe5 25. Bxe5 Re8 26. Qg4 Qg6 is losing for white...
b) 22. Nf6
b1) 22...gxf6 23. Rxd5 (threatening to win the Rd7 and weakening the f6 square)Rxd5 24. Bxf6 Nxe5 and there is nothing...
c) 22. Bf6
Too lazy to calculate, and this move wich has no quick threat. Of course Black would be nice to take the bishop with the Nd5 but they are not compelled...
c1) 22... gxf6 (Blacks are nice) 23. Rxd5 (i love this move) Rxd5 (23...Nxe5 24. Rxe5 followed by 25...Nf6 etc) 24. Nxf6 + Qxf6 25. Qxf6 Rxd5 26. Qxa6 with material advantage.
c2) 22... Nxf6 (Blacks are very nice) 23. Nxf6 gxf6 24. Rxd7 with advantage (R vs N).
But as i said before, Black is not force to take the bishop in f6...
O.K. i find this one hard.
|Jun-28-08|| ||vesivialvy93: didn't came close to solve this one !
i was looking for Nf6+...lol
|Jun-28-08|| ||vanytchouck: Ok, i miss the strength of 22. Bf6 but according to Fritz 10 : |
The best line is
22. Bf6 h6 (not Kh8) 23. Qg4 g6 24. Qh4 h5 25.Rac1 (euh ...) Nxb2 26. Qg5 Kh7 27. Rxc5 Qe6 28. Qd2 Qf5 29. Rxd5 with an evaluation of (+ - 2,86)
The point is that F10 finds 22...h6, 22...Nxe5, 22...Nxf6 and 22...gxf6 much better than 22...Kh8.
And the computers are much better in calculation...
|Jun-28-08|| ||dzechiel: <Samagonka: <dzechiel>: Suffice to say I was so far off base tonight that I scrapped everything.|
You must have been miles away because this one seems not as difficult for me as it is rated. Anyhow, I am still curious to know where exactly you went wrong?>
I persuaded myself that the key move must be 22 Rxd5 and it went downhill from there.
|Jun-28-08|| ||Marmot PFL: 1st idea - 22.Nf6+ gf6 23.Bxf5 Nxe5 and black looks OK. The tempting 22.Rxd5 also fails to the same defense. So 22.Bf6 is interesting, threatening Ng5. The critical line is 22...gxf6 23.Nxf6+ Nxf6 24.ef6 (threatening Qg5+ and mate as well as Rxd7) Rxd1+ 25.Rxd1 Kh8 and here I missed the fairly simple 26.Qg5 Rg8 27.Qxg8+ Kxg8 28.Rd8 mate. Also the game line I didn't really analyze either, but the positions after g6 are not so hard as the dark squares are permanently weakened without white even having to invest material. |
BTW I would like to request that kibitzers refrain from calling the loser's moves "blunders" unless they can suggest real improvements rather than just different ways to lose.
|Jun-28-08|| ||DarthStapler: I didn't get it|
|Jun-28-08|| ||lost in space: <Jimfromprovidence> I don't think that 21... Re8 is better than the text (21...Nc4). White can win nearly the same way as in the game:|
From your diagram:
22. Bf6 h6 (the best move I found) 23. Bxg7 Kxg7 24. Nf6 Nxf6 (the best move I found) 25. exf6+ Qxf6 26. Qxf6 Kxf6 27. Rxd7 with advantage in the endgame.
or 22. Bf6 h6 23. Qg4 g6 (forced) 24. Qh4 h5 (forced) 25. Qg5 Kh7 (foreced) 26. Be7!! and Black can resign. Also 26. g4 looks good enough for a win for white.
|Jun-28-08|| ||Jimfromprovidence: <lost in space>
<I don't think that 21... Re8 is better than the text (21...Nc4). White can win nearly the same way as in the game:
From your diagram:
22. Bf6 h6 (the best move I found) 23. Bxg7 Kxg7 24. Nf6 Nxf6 (the best move I found) 25. exf6+ Qxf6 26. Qxf6 Kxf6 27. Rxd7 with advantage in the endgame.>
Your line looks real solid. Well done!
|Jun-28-08|| ||PinnedPiece: <Patzer2 .."(pseudo) sacrifice"> What other kind of "piece give" is there...a real sacrifice where you get nothing back? In other words, a mistake?|
|Jun-28-08|| ||mmmsplay10: well its only a pseudo sac if you get the material back. If you checkmate the opponent, than it is a normal sac. or a gambit is a pawn sac that you dont get material back, (or at least right away)|
|Jun-28-08|| ||PhilFeeley: I knew that f6 was the key square. The question was whether to occupy forst with the bishop or the knight. When I saw the solution, I remembered something Spraggett teaches: queens work better with knights, rooks with bishops. I don't know why this is true or whether most GMs even agree with it. (http://www.kevinspraggett.com/)|
|Jun-28-08|| ||TrueBlue: did anyone else complete the survey? I did, spent about 30 minutes doing it, and as you can see, no premium membership for me :) I was just redirected to the yahoo web page at the end, no thank you, no 3 months premium membership. If it was google, that's fine, but yahoo!?!?!?|
|Jun-28-08|| ||patzer2: <mmsplay10> Your definition of a "normal sacrfice" is clever and interesting, but is not in standard use. A sacrifice leading to mate is actually a pseudo or sham sacrifice, since mate is the ultimate advantage one can gain from a pseudo sacrifice in a combination.|
|Jun-28-08|| ||patzer2: <pinned piece> Rudolph Spielmann in his 1935 classic work "The Art of Sacrifice in Chess" first made the distinction between "real" and "sham" or temporary sacrifices. He said a "sham" sacrifice was one that involved no risk, since "after a series of forced moves, the player either recovers the invested material with advantage, or else even mates his opponent."|
Spielmann grouped "sham sacrifices" into three categories:
1. Positional sacrifices
2. Sacrifices for gain (i.e. of material)
3. Mating sacrifices
As far as I know, that classification remains the standard. However, "true sacrifices" or simply "sacrifices" are the terms often used today to describe Speilmann's "real sacrfices."
Also, the term "pseudo sacrifice" is often used interchangeable for the term "sham sacrifice." More often than not, modern Chess authors simply refer to "combinations" or "forced" moves without use of the terms "sham" or "pseudo" sacrifice.
|Jun-28-08|| ||patzer2: <pinned piece> To help answer your question, a "real sacrifice" is one where the outcome is not clear and involves some element of "risk" as suggested by Spielmann. However, it is not a "blunder," anymore than gambling is an investment. |
Spielmann wrote "In real sacrifices the player gives up material, but is unable to calculate the consequences with accuracy; he has to rely on his judgment. He obtains dynamic advantages, which he can realize gradually. Should he not succeed in this he will most probably lose the game through deficiency in material. Therin lies the risk, and risk is the hallmark of the real sacrifice."
|Jun-28-08|| ||patzerboy: Nice puzzle. Rxd5 is so blindingly obvious...and so wrong! This is a good example of "look (thoroughly) before you leap (to the wrong conclusion)."|
I missed it, of course.
|Jun-28-08|| ||zb2cr: Looks like I'm in good company...I also went for 22. Rxd5, with the idea of destroying or luring away guards for f6.|
|Jun-28-08|| ||LivBlockade: <al wazir: But I think the line actually played shouldn't win either after 26...h5, preventing the from going to g4.>|
Maybe after 26...h5 White would play 27. Ne6, threatening both Nxf8 and Qh6+, and now Black does not have ...g5 as a defense.
|Jun-29-08|| ||al wazir: <LivBlockade: Maybe after 26...h5 White would play 27. Ne6>|
Brilliant! That's undoubtedly it. Thanks.
I'm surprised no one else mentioned this, but I bet Popovic was aware of it.
|Jun-29-08|| ||PinnedPiece: <patzer2: <pinned piece> To help answer your question, a "real sacrifice" is one where the outcome is not clear and involves some element of "risk" >|
thx patzer2. in other words, there are pseudo sacrifices, and then there are other piece giveaways that either work, or many cg.com kibitzers will call a blunder. (I can only spot the most obvious blunders, myself...)
|Jun-29-08|| ||CapablancaFan: Here's an example, of a recent GOTD that displayed a "real" sacrifice. Hector vs J Carstensen, 2003|
|Jun-30-08|| ||al wazir: <patzer2: To help answer your question, a "real sacrifice" is one where the outcome is not clear and involves some element of "risk.">|
I believe that most chessplayers also use the term "sacrifice" for what you call a "pseudo-sacrifice" and distinguish what you call a "real" sacrifice by calling it "speculative" (or "positional"). You're entitled to use any terminology you like, of course, but if your terminology is unconventional you risk confusing others.
And since our wetware and even our software is imperfect, it is sometimes unclear after the fact whether a sac leads to a forced win, i.e., whether it was "real" or "pseudo" -- whereas the player who made it, if he is honest, can always tell you if it was speculative.
|Jun-30-08|| ||Once: <patzer2> <al wazir> I have seen chess writers use both meanings of the word "sacrifice" - either a genuine investment of material for uncertain gain (<patzer2>'s definition) or any investment of material (<al wazir>'s definition).|
Bobby Fischer used to say that he loved facing the sicillian dragon because he had the approach down to a fine art - "sac, sac, mate". But you might argue that a sacrifice leading to a mate is not a sacrifice at all.
Then again, "pseudo sac, pseudo sac, mate" does not sound so snappy.
I think this is an area where chess terminology is ambiguous. There is no right or wrong answer, just different interpretations.
Is Deckard a replicant? Some say definitely yes, some say definitely no. I say that Ridley Scott (and before him Philip K Dick) deliberately left this ambiguous, so that we would think about the nature of humanity.
<patzer2> <al wazir> I respect both of you for the quality of your posts here, so I can live with either definition. I know what you mean.
|Jun-30-08|| ||ravel5184: <234> White to play. 22. ? was Saturday's puzzle.|
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