< Earlier Kibitzing · PAGE 3 OF 3 ·
|Jul-20-07|| ||Tactic101: Great puzzle! Bxg7! and black can't defend two focal points (h8 and h7). And the rook check means naught. Very instructive.|
|Jul-20-07|| ||SaltiNeil: Can someone tell me why black plays 10...Nfd7 instead of Ngd7? I think that is where all the trouble started.|
|Jul-20-07|| ||Tactic101: Beats me. Nfd7 can't be a good move, that's for sure. But then again, it took white absolute precision and a few sacs to win.|
|Jul-20-07|| ||Edmemphis: Got this one pretty quickly. Nice sac, white had all the elements there to spring this one on black.|
|Jul-20-07|| ||melianis: Nfd7 is a sometimes the only good move, at some Old Indian line (also in some of the Benonis?), if I remember correctly, obviously not here. It's been a while since I read the opening book, so'm not certain of those.|
|Jul-20-07|| ||alexandrovm: How about 17. Ne6?|
|Jul-20-07|| ||realbrob: I don't want to be arrogant, but why was this puzzle difficult? The first move was quite intuitive, if Black had his d3 pawn on d7 it would be a nice Monday puzzle, mate in 2 - 17.Bxg7. |
The situation is a bit more complicated because Black can check the White king with tempo, creating a flee square for his own king. It doesn't change the substance, though - 17.Bxg7 Re8+ 18.Kf1 Bxg7 19.Qxf7+ Kh8 here I thought of 20.Ne6 Qe7 21.Qh5+ if 21..Kg8 22.Qh6 if 21..Bh6 22.Rg6, Black looks quite busted.
|Jul-20-07|| ||zb2cr: Got it! About 90 seconds. I really like the forcing nature of 17. Bxg7. After the "spite check" 17. ... Re8+; 18. Kf1, White has mate threats by Qh8#, Qh7#, and Qxf7#. Black's 18. ... Bxg7 removes the immediate mate threats, but White can still play the obvious 19. Qxf7+, Kh8; 20. Qh5+, Kg8; 21. Qh7+, Kf8. About here is where I stopped the analysis, considering that White had too many threats, such as the potential fork + clearance sacrifice 22. Ne6+, and 22. Rf3+. In a game I would most likely have played the latter move rather than the beautiful actual line.|
|Jul-20-07|| ||Fezzik: @<r00723r0>
Thanks for the correction, I simply missed the move number. I was thinking of 22.Qe7 instead of 23.Qe7. Remember, I didn't even consider 22...Ne6 as possible, but I did see that there was more than one way to mate if Black didn't defend g7.
|Jul-20-07|| ||bogo78: <alexandrovm: How about 17. Ne6?> I believe its a little too precipitated. Remember white is already down one piece so to drop another ♘ without immediate compensation would amount to losing. 17...fxe6 and i don't really see any serious threats from white. Let me know what you had in mind now.|
|Jul-20-07|| ||Rodrigo Gutierrez: Didn't quite get it. I saw 17. Bxg7 immediately but discarded it because of 17... Qe7+ 18. Kf1 Qe2+ (this is why I think this problem is not trivial); only checking the kibitizting after did I see that 17... Qe7+ is answered by 18. Re3 and black is lost. So I settled for 17. 0-0-0 (17. Ne6 does not seem to get white anything after 17... fe6 because now black can play 18...Bxg7 safely since 19... Qf6 will follow).|
|Jul-20-07|| ||pggarner: Intersting way to handle the Caro-Kann. Is 7.c5 the normal move in the Panov variation? It seems to relieve the pawn-tension in the center too early.|
|Jul-20-07|| ||alexandrovm: <bogo78: <alexandrovm: How about 17. Ne6?> I believe its a little too precipitated. Remember white is already down one piece so to drop another without immediate compensation would amount to losing. 17...fxe6 and i don't really see any serious threats from white. Let me know what you had in m|
|Jul-20-07|| ||kevin86: I really liked this one! White attacks at black's strongest point-so it seems. Instead,the sacs and mate threats open up black's king position like a bomb would.|
|Jul-20-07|| ||tatarch: 22.Ne6+ and 23.Rxg7 is really the whole puzzle here-- or at least seeing that 5 moves in advance is. The rest of the moves seemed (relatively) straightforward to me.|
|Jul-20-07|| ||Gregor Samsa Mendel: <Madman99X> Thanks for looking into 20 Ne6. Since it does seem to win after all, I'll tell myself that this is the first Friday puzzle I've solved since I don't know when. :)|
|Jul-20-07|| ||Crowaholic: Difficult, ok... so 17. Bxg7 isn't as easy as it seems? What defenses work against the dual threat of Qh7# and Qh8#?|
17. ..Bxg7 18. Qh7# doesn't cut it.
17. ..Bxg5 18. Qh8# neither.
Nor 17. ..Kxg7 18. Qh7#
17. ..Re8+ - this is more interesting. 18. Kf1 but now ..Kf8 19. Qxf7# - no. Better is 18. ..Bxg7 19. Qxf7+ Kh8 and now 20. Ne6 Qe7 maybe? 21. Qh5+ Kg8 22. Rxg7+ Qxg7 23. Nxg7
hmmm... let's count some material. White started out a piece for a pawn down.
White won ♙♗♕, totalling 14 points, for ♗♖♘, totalling 11 points. Therefore, White is now nominally a pawn up instead of two down. While that isn't bad, I'm not sure whether it is sufficient.
Black could also have played 20. ..Re7. Let's see...
20. ..Re7 21. Qh5+ Kg8 22. Nxd8 Nxd8
White won ♙♕ for ♘♗, a +5 point gain. Not good for Black.
Still I'm wondering whether White can mate. 17. Bxg7 Re8+ 18. Kf1 Bxg7 19.
Qxf7+ Kh8 20. Qh5+ Kg8 21. Qh7+ Kf8 22. Ne6+ Rxe6 22. Rxg7... hey... this could be going somewhere. How does Black stop *this* mate? Only 22. ..Rxe6 is not forced, as far as I can see, but White at least wins the queen if the sac is declined. But this may not be sufficient.
After 22. ..Kf7 23. Nxd8+, I see things going downhill for Black quickly.
22. ..Ke7 23. Qxg7+ Kxe8 24. Re1+ Nce5 25. Rg6+ Qf6 26. Rxf6+ Nxf6 27. Rxe5# is quite unpleasant for Black, too.
25. ..Kf5 and now, boy it gets tough... very complex position. I gave in to the temptation of asking my computer for help at this place, and it tells me there is: 26. g4+ Nxg4 27. Rg5+ Kf4 28. Rxg4+ Kf3 29. Rg3+ Kf4 30. Qg4#.
Enough for today. Looking at the solution...
Oh, ok, Pomar-Salamanca decided to die a quicker and simpler death. I got the text line without using a board, i.e. there is some chance I would see it in a game. And my computer taught me an interesting mating trick today in the 22. ..Ke7 line.
|Jul-20-07|| ||beginner64: Does black lose immediately after 13.. gxh6?
|Jul-20-07|| ||Crowaholic: To clarify: I didn't see the "see-saw" immediately, but at one point I wondered: Hmmm, Qxf7+ or Qh7+? Then it occurred to me I could have the cake and eat it, too, by moving the queen in a triangle with check as seen in the game.|
Bxg7 was very easy to see, but there are some complex follow-up lines.
|Jul-20-07|| ||YouRang: Oh well, 4 for 5 isn't bad. :-|
I thought it might be 17. Nh7, since we threaten black's rook and bishop, we protect our bishop, and the knight is immune since 17...Kxh7? loses very rapidly to 18. Bxg7.
Unfortunately, if black doesn't eat the poison, he feeds it back to me with 17...Rd1+.
Too lazy today. I should have considered 17. Bxg7, but I didn't. Even so, I doubt that I would have found the whole line anyway.
|Jul-20-07|| ||MostlyAverageJoe: <Crowaholic: Bxg7 was very easy to see, but there are some complex follow-up lines.>|
Which ones? Specifically, what do you see that the black could do to complicate the game?
|Jul-20-07|| ||fm avari viraf: White is on an attacking spree & Black's vulnerable fortress is about to crumble with 17.Bxg7 Re8+ 18.Kf1 Bxg7 forced as White was threating mate. Now, it's very easy for White to finish off Black's feeble defense with 19.Qxf7+ Kh8 20.Qh7+ Kf8 21.Ne6+ Rxe6 22.Rxg7 & White mates in 2 moves 22...Ke8 23.Qg8+ Nf8 & 24.Qf7# or 22...Nf6 23.Qh8+ Ng8 & 24.Qxg8#. Though it was 3 star but the solution seems to be predictable.|
|Jul-20-07|| ||Crowaholic: <MostlyAverageJoe: Which ones? Specifically, what do you see that the black could do to complicate the game?>|
To quote from your post:
<21 ... Rxe6 (this is the second best, allowing mate in four. Best move, Ke7, would allow mate in 7) BZZZT - this is the variation I missed>
I found the forced mate in this variation hard to find. The black king is in trouble but quite well-defended. It's also easy to slip up, for example, 27. Rxg4 (without the zwischenzug Rg5+) in the 23. Qxg7+ line actually loses to 27. ..Rxe1+ and White cannot recapture because of 28. Kxe1 Qe8+ 29. Kf1 Qe2+ 30. Kg2 Qxg4+ 31. Qxg4+ Kxg4 . If you're willing to settle for a quick material gain, it's easy, though, just don't bother about the (assumed) mate and play 23. Nxd8 Kxd8 24. Qxg7
However, that's the only line that caused me major problems so maybe I should have used the singular: There was one complex follow-up line, and it wasn't necessary to win - there are prosaic alternatives with slower but simpler wins. But it was necessary to find best play. I missed two aspects of best play after the part I got: 17. Bxg7 Re8+ 18. Kf1 Bxg7 19. Qxf7+ Kh8 20. Qh5+ Kg8 21. Qh7+ Kf8 22. Ne6+ Ke7. First, I considered 23. Qxg7+, which is mate in 7 whereas 23. Rxg7+ is mate in 6. Second, I missed the last 4 moves to mate in the 23. Qxg7+ line. Sure, I would have eventually found them given enough time (something I hardly ever have), but it was - subjectively - not so easy.
Hmmm. maybe the 23. Rxg7+ line is actually not only shorter but simpler, then it was just an oversight on my part:
23. Rxg7+ Kxe6 24. Qg6+ Qf6 25. Qxe8+ Qe7 26. Re1+ Nde5 27. Rxe5+ Nxe5 28. Qxe7+ Kf5 29. Qxe5#
|Jul-20-07|| ||Magic Castle: <mostly average joe crowholic> Which game are you discussing? In this game 23. Rg7 is not a check. The threat of 24. Qh8 and 24. Qg8 could not be defended. Maybe only delayed by a black rook sacrifice 23...Re1+ 24. Re1 and then by a knight move (24...Nf6 25. Qh8+ Nf8 26. Qg8#. Any other move will not delay mate in one, either by Qh8 or Qg8 in case of a 24.....Qh4. After the key move 17. Bg7. (So the discussions should really be where black made a mistake before 17. Bg7) Everything seemed forced after 17. Bg7. Initially the double mate threat was at h8 and h7 whereupon the black rook needs to move away by Re8+. There seemed nothing more for black to stop the succeeding checks at f7 and h5 in the face of a Qh8#. So Bg7 is really forced. The only move where black seem had a choice is in Ne6+ where he can opt to sacrifice his queen by Ke7 and prolong his agony by a few more moves.|
|Jul-20-07|| ||Crowaholic: <Magic Castle: Which game are you discussing? In this game 23. Rg7 is not a check.>|
The "main line" (I mean the line that follows from best play*) starting from the puzzle position and proceeding as in the game played, but then diverting with 22. ..Ke7. 22. ..Rxe6 as in the text is a (theoretical) mistake that gives White a significantly shorter and simpler mate than 22. ..Ke7. It is somewhat understandable that Black did not want to play ..Ke7 because White can just take the queen and win the endgame easily, on the other hand, 22. ..Rxe6 23. Rxg7 is very obvious and there is no escape. I think Black should have played 22. ..Ke7 or resigned on the spot. Maybe Black was hoping for 23. Qxg7+?? where White's advantage is much smaller.
<Magic Castle: The only move where black seem had a choice is in Ne6+ where he can opt to sacrifice his queen by Ke7 and prolong his agony by a few more moves.>
This is the line I was referring to. Sorry for the confusion. The catch is that if White goes for a quick mate rather than just grabbing the queen, then things get a little complicated. But it can be done, as I detailed at the end of my previous post.
*) Best play means that the losing side goes for the longest mate, the winning side goes for the shortest mate, and both sides never make a losing move from a drawn position. I.e. this is roughly how a computer would judge the moves.
< Earlier Kibitzing · PAGE 3 OF 3 ·