< Earlier Kibitzing · PAGE 2 OF 2 ·
|Dec-21-08|| ||johnlspouge: < <whitebeach> wrote: Well, I saw 12. Rxd6, but I only anticipated 12...Bd6 in reply. So I can't even say I came close. >|
Often, the best play is to refuse a sacrifice. I terminate calculation with the win of a P (Kotov's Rule), so by my standard, you are fine. Generally, I insist on justifying a sacrifice by following the corresponding position to a material advantage in a quiescence position, although some positions (particularly, Q+R chasing K, and K in the center of the board) exceed even my fondness for calculation.
By the way, irritated by my own lack of clarity, I left a variation for you on yesterday's puzzle.
|Dec-21-08|| ||JG27Pyth: <xrt999: after 14...Bxd6 I get:
15. Qxd6 Qd8
16. Qxe6+ Qe7
17. Bxf7+ Kf8
18. Qxe7+ Kxe7
19. Bd5 Rab8>
I think you've followed the board wrong. Your notation 19...Rab8 doesn't make sense which leads me to believe you misplaced that rook when you analyzed the line... there's a rook on c8, so if 16...Qe7 white has 17.Qxc8+
|Dec-21-08|| ||johnlspouge: < <tallinn> : I think the key move to see is Bh5. >|
I enjoyed finding this second key candidate move (appearing in my Variation (3)), too. Most Sunday puzzles have a second candidate.
|Dec-21-08|| ||johnlspouge: < <whiteshark> wrote: <realbrob> I like the French accent in your pun. :D >|
|Dec-21-08|| ||JG27Pyth: @JohnLSpouge <(3) 12…Bxd6 13.Qxd6 (threatening 14.Qxc6+ and 14.Bh5 15.Qxe6+)|
Note: the Black Ke8 is stalemated. Moreover, Bg5 pins Nf6 to the mate threat Qe7#.
Black loses material and has no counterattack.>
I only looked at the sac accepted, and I still don't see why Black declined... instead of the variation quoted above, what about:
12…Bxd6 13.Qxd6 Qb6 14.e5 Rd8 ...
I don't see how white continues.
|Dec-21-08|| ||mmmsplay10: Rxd6 Bxd6
Qxd6 (idk) Bd7
click for larger view
|Dec-21-08|| ||johnlspouge: < <JG27Pyth> wrote : 12…Bxd6 13.Qxd6 Qb6 14.e5 Rd8 ... [snip] I don't see how white continues. >|
Black gets some pull after 14.e5, so it is not a good move. As a matter of style, I abbreviate my long-winded analyses with threats, and in my Variation (3), 13...Qb6 does not meet the threat 14.Bh5 15.Qxe6+.
I cannot take responsibility for <your> variations, <JG27Pyth> :)
|Dec-21-08|| ||johnlspouge: < <mmmsplay10> wrote: [12.] Rxd6 Bxd6 [13.] Qxd6 Bd7
[14.] Rd1 Rd8 then what? >
I inserted the move numbers you omitted. If White plays 14.e5, Black goes down in flames.
My chessforum contains detailed instructions on how to download the analysis engine Toga II 1.3.1, which can answer this type of question.
|Dec-21-08|| ||johnlspouge: As usual, I missed the best defense, 12.Rxd6 <Rc8> according to Toga. Another variation seems to complete the analysis:|
(4) 12…Rc8 13.Bxf6 (threatening 14.Bh5 15.Rxe6+)
13…gxf6 [13…Bxd6 14.Qxd6 gxf6 transposes]
14.Bh5 Bxd6 15.Qxd6 (threatening 16.Qxe6+ 17.Bh5)
17…Qc7 16.Qxe6+ Kf8 17.Qxf6
White has B+3P for R and an open K.
|Dec-21-08|| ||bullsbehad: To those that said "this is easy" or "too easy for Sunday," please go and claim your title of World Champion, then enlighten us why its "so easy." Who are you helping anyways with these comments? |
My pathetic analysis started at 12. Rxd6 as my first guess (considering it seemed so wrong, I correctly figured that had to be it for a CS puzzle), but making it work (i.e. 12...Bxd6) 12 moves through and then understand why Black would then resign at 23... is beyond my wildest dreams to comprehend. I flirted with e5, but again was swearing silently. Finally I gave in and peaked...then at move 14, I was like "I see it now...!!!"
Then 16., "ah perhaps that is it!"
16..."damn not it"
At last 21.? "Nope..."
Finally 23...1-0?!? "Merde!!!" (I am not French)
Long story short, if you say this is easy, back that up like johnlspouge would. WWJD anyone? Your analysis sir, is quite helpful.
This was easy? ...I beg to differ.
|Dec-21-08|| ||beginner64: Wow, great puzzle. I got the first few moves, but for move 18, I decided to forego the knight, and go with 18. Rxf6. The threat there is the obvious Rxf7+, or non forcing Qe7 with the threat of Qxf7#. I don't know if 18. Rxf6 is a sound continuation yet or not, but I am going to check through all kibitzing now to find that out.|
|Dec-21-08|| ||agb2002: Black is threatening ... Nxe4 and ... b4, but his king needs at least two moves to castle. White can take advantage of this is he is able to find a way of opening lines against the black king. Therefore, 12.Rxd6:|
A) 12... Bxd6 13.Qxd6
A.1) 13... Qb6 14.e5 Rd8 15.Qb4 a5 16.Qh4 Nd7 17.Bxd8 Qxd8 18.Qxd8+ Kxd8 19.f4 Bxg2 20.Rg1 Bc6 21.Rxg7 with advantage.
A.2) 13... Bxe4 14.Nxe4 Rd8 15.Qc6+ and 16.Nxf6 or 16.Nc3 with 2B+P vs R.
A.3) 13... Bd7 14.e5 and the knight is lost.
A.4) 13... Bb7 14.e5 Rd8 (14... h6 15.exf6) 15.Qc5 Rc8 16.Qa7 Qc7 17.exf6 b4 18.fxg7 Rg8 19.Bxa6 bxc3 20.Bb5+ Bc6 21.Bxc6+ Qxc6 22.Qe7 mate.
B) 12... Bxe4 13.Bf3 Bxf3 14.Qxf3 Rc8 15.Rc6 and White seems to have the better chances.
That’s all I can do at this moment. Time to post and check.
|Dec-21-08|| ||mig55: Dear folks,"echt" is dutch and not german..|
|Dec-21-08|| ||goodevans: Strange sort of Sunday this. Checked it out this morning and very little kibitzing, and now again at the end of the day (UK time) and not much more. Why is this? I guess because (a) the Rxd6+ sac was so obvious, and (b) working out whether it works is so difficult.|
To me the other big question I was wrestling with this morning was whether to play the sac straight away or exchange B for N (12 Bxf6) first. I was worried about moves like 12 Rxd6 Nxe4 which looked really messy, but I see now that johnlspouge has posted a refutation to that line.
In a game, if I’d have been brave enough to play the sac at all then I think I’d have traded B for N first. Would this have been wrong?
|Dec-21-08|| ||johnlspouge: < <goodevans> wrote: [snip] To me the other big question I was wrestling with this morning was whether to play the sac straight away or exchange B for N (12 Bxf6) first. >|
I looked at 12.Bxf6 as well, so I put it through Toga. It yields a little pull for White, but no win. I rejected it, because (as in the game) the White dark square B squeezes the Black K.
|Dec-21-08|| ||dzechiel: White to move (12?). Material even. "Insane."
The move that immediately announces itself to me is
But that's about as far as I want to take it. Should black capture the rook with
leans on the remaining black bishop and gives white time to play 14 e5. But the fly in the ointment is the fact that black is not obligated to take the rook. He can choose to move the light squared bishop, or protect said bishop with the queen or rook.
I wish I had more time to work on this. Time to check and see how it all went down.
|Dec-21-08|| ||TheBish: The only thing I'm looking at is 12. Rxd6!, which I believe leads to a winning attack. Can't see it to a conclusion (which helps to make it insane), but I would call it an intuitive sacrifice, since if 12...Bxd6 13. Qxd6, not only doesn't Black ever castle, but White is threatening not only 14. Qxc6+ but also 14. e5. One defense is 12...Nxe4 13. Nxe4 Bxe4, but it looks like that can be met strongly by 14. Rhd1, threatening 15. Rd8+ and also with ideas of 16. Qe5 planning 17. Rxe6+. If Black declines the rook offer (wise), with either 12...Bb7 or 12...Rc8, White should continue 13. Bxf6 gxf6 14. Bh5!, threatening 15. Rxe6+. Beyond that, I can't see it to conclusion (probably a dozen or so moves to go), but it looks like a crushing attack, with White winning the e6 pawn along the way in many lines.|
|Dec-21-08|| ||MaczynskiPratten: It's been an interesting week - the theme seems to have been that a one-mover intuitively jumped out of each position as soon as you looked at it. BUT .. on some days the followup was so complex as to be almost incalculable (Thu, Sun), in one case the intuitive sacrifice didn't work due to a sucker counterpunch (Wednesday's "spoiler") and on Sat the intuitive move nearly works (fxg6) but there is a much stronger move available (Re1). And Fri was an endgame where the first move looked fairly obvious but it wasn't easy to see exactly why it was best - a subtle zugzwang. Altogether, a nice mix, thanks Chessgames (as always).|
|Dec-21-08|| ||PinnedPiece: I really think that taking the Rook at move 12... holds out longer but definitely loses.|
12...Bxd6 13.Qxd6 Bd7 14.Rd1 0-0-0 15.e5 h6 16.exf6 hxg5 17.fxg7 Rhg8 18.Nd5 exd5 19.Rxd5 g4 20.b4 Qa3+ 21.Kb1 Kb7 22.Rd3 Qa4 23.Qe7 Kc8 24.Bxg4 Bxg4 25.Rxd8+ Rxd8 26.Qxd8+ Kxd8 27.g8=Q+ Ke7 28.Qxg4
click for larger view
|Dec-21-08|| ||njchess: I got this one. I think White's 15. Bh5 was the most difficult part of the puzzle. I'll post more tomorrow when I have time.|
|Dec-21-08|| ||zzzzzzzzzzzz: i got it.|
|Dec-22-08|| ||zzzzzzzzzzzz: i think white only has + = after rxd6 but after rxe6+ he has+ -|
|Dec-22-08|| ||njchess: I think for most who analyzed this position, Rxd6 was at least a possibility. Most I think examined it in the context of 12. Rxd6 Bxd6 13. Qxd6 Qb6, and, if it was rejected, it was because the resulting position didn't justify exchanging a rook for a pawn and a bishop. I disagree.|
The following position results after 12. Rxd6 Bxd6? 13. Qxd6 Qb6:
click for larger view
Black cannot castle much less get his king side rook into the game from this position. He has already spent a move (Qb6) defending hanging pieces and will need to spend more to secure his king. After 15. Bh5! Qb7 16. Qxe6+ Kf8 17. Qd6+ Kg8 Black's other central pawn falls.
13. ... Rc8 is slightly better for Black but is still losing (e.g. 12. Rxd6 Bxd6 13. Qxd6 Rc8 14. e5! Qc7 (best?) 15. Qxc7 Rxc7 16. exf6 Rg8). White has a bishop, a knight and a pawn for his rook, and the better position.
To Black's credit, I think he saw Bxd6 as intuitively bad and played 12. ... Rc8. Also playable was Bb7, but backward bishop moves can be difficult to see, and Black may simply have wanted to get his rook to the half open c-file.
After 13. Bxf6 gxf6 14. Bh5! must have been a shock for Black. It's tough to see moves from the rear like that especially when all the action is happening right on your doorstep. 14. ... Bh6+ is a natural reply if you have already concluded that Bxd6 is losing. At this point, Black is headed for a bad endgame position at best.
15. Kb1 b4? is a costly mistake. Black thought to perform a nifty tactical fork with his pawn and queen, but defending his king should have been the priority. The text move also shows that he completely missed the subtle Rxe6+. Slightly better would have been Ke7, though e5 would be a concern.
The more forceful 17. Qd6+ is played by White over the quieter but equally sound Qf3. From there, Black is forced to trade pieces as well as lose pieces in exchange for protecting his king. At the end, down four pawns, Black resigns.
This game also illustrates how far Najdorf theory has progressed. 7. Qf3 is played with the intent of moving the queen to g3. It is little played because White will usually need to play f4 at some point, and committing the queen this early in the game is premature.
Black's reply of 7. ... Bd7 is even more unusual. h6, Nbd7 are the more common responses. Be7 is also playable. The text move forces Black to play Nc3 if he wants to develop his knight. I'm not a fan of 9. ... Qa5 because 1) after 10. Bxf6 gxf6 11. Qxf6 Qe5 12. Qxe5 Bh6+ 13. Kb1 Nxe5 14. Rhf1 I think White is better, and 2) it also allows White to play Qg3 without loss of tempi. Better is Be7.
|Dec-24-08|| ||patzer2: For the Sunday Dec 21, 2008 puzzle solution, White exploits the weak Black King position with the exchange sacrifice 12. Rxd6!! |
|Jan-02-09|| ||xrt999: < JG27Pyth: I think you've followed the board wrong. Your notation 19...Rab8 doesn't make sense which leads me to believe you misplaced that rook when you analyzed the line... there's a rook on c8, so if 16...Qe7 white has 17.Qxc8+>|
Ok, sorry about that, I misplaced the rook when I set the board up,,,
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