< Earlier Kibitzing · PAGE 3 OF 3 ·
|Jun-02-10|| ||vsadek: <Once>
Thanx for your post. I've enjoyed reading it. :)
|Jun-02-10|| ||JG27Pyth: Got it, but I've been seeing a lot of this theme recently, due to Nakamura vs Y Shulman, 2010 and also I've been working thru Pachman's Modern Chess Strategy -- the chapter on rooks -- which gives the ultimate example of a Queen decoy from the back rank, E Z Adams vs Carlos Torre, 1920.|
|Jun-02-10|| ||patzer2: The poisoned Queen sham sacrifice 26...Qd6! creates a winning double attack threat, which drives the helpless Rook off the open file and wins a piece.|
If 26...Rxd6??, then it's mate-in-two with 27. Re1+ Kh2 28. Rh1#.
|Jun-02-10|| ||zb2cr: Rotgut. For some reason, I was too focused on getting the Rook to the h-file for mate on h1. I never saw that if Rxd6, ... Re1+ turns the mate sideways!|
|Jun-02-10|| ||Marmot PFL: wow, this took a while. finally decided it had to be something that looked dumb but wasn't and found 26...Qd6.|
|Jun-02-10|| ||tarek1: It took me forever to hit on the right idea.
I got many week-end puzzles quicker than this one.
The plan of Qc6 and/or a rook sacrifice on g3 haunted me, I couldn't get my mind off it.
Of course it has to do with the diagonal but in a different way :
The point is of course : <27.Rxd6 Re1+ 28.Kh2 Rh1#>
The queen is taboo, and it is also forking the rook and the knight on b4.
So let's say <27.Rc1> then simply <27...Qxb4>
White doesn't have any counterattacks or useful checks, <27.Nc6+> or <Nd5+> simply loses the knight one move earlier.
<27.f3> simply loses to <27...Qxd1+> and a quick mate.
|Jun-02-10|| ||johnlspouge: Wednesday (Medium/Easy)
Z Nilsson vs Book, 1946 (26…?)
Black to play and win.
Material: B+P for N. The White Kg1 has 4 legal moves, 2 x-rayed by Bb2. It is vulnerable to Qc7xg3+ and Re4-e1+. The White Rd1 bears the absolute burden of preventing 26…Re1+ 27.Kh2 Rh1#. Black can overload Rd1 to his advantage, because both Nb4 and Rd1 are loose. The Black Ke7 is vulnerable to checks from all 3 White pieces, and the Black Qc7 bears the absolute burden of preventing a Dovetail mate Qh8-d8#.
Candidates (26…): Qd6
26…Qd6 (threatening 27…Qxd1+ or 27…Qxb4)
(1) White cannot accept the sacrifice:
27.Rxd6 Re1+ 28.Kh2 Rh1#
(2) White can try to save Rd1 (TRIP), but taking fails as above, running fails to 27…Qxb4, interposition fails to 27.Nd5+ exd5 or 27.Nd3 cxd3, and protection is not possible.
Amazingly, White’s threat of dovetail mate has also vanished with the d-file.
|Jun-02-10|| ||awfulhangover: What a shame. Missed it by starting with -a5 and silly calculations. I miss last week:-)|
|Jun-02-10|| ||dukesterdog2: Finally got one right this week! It took me a couple minutes, but I eventually noticed white suffers from back rank weakness that prevents his rook from leaving the first rank. After seeing that, Qd6 forking the rook and knight became obvious.|
|Jun-02-10|| ||doubledrooks: 26...Qd6 leaves white between a rock and a hard place, because 27. Rxd6 Re1+ 28. Kh2 Rh1 is mate. If the rook moves off the d file then 27...Qxb4.|
|Jun-02-10|| ||kevin86: Two very coy and sharp moves by black.White couldn't take the queen because of mate. The rook is chased away and the second lethal blow falls.|
|Jun-02-10|| ||Jimfromprovidence: As <lost in space> pointed out, the tempting 26...Qa5?!, loses to 27 Qb8.|
click for larger view
Now white has two threats. The first is Qxb7+. In addition, his knight is safe because if the black queen moves off of the a5-d8 diagonal, then Qd8#.
Black has to sacrifice rook for knight in this position with 27...Re1+ 28 Rxe1 Qxb4.
click for larger view
|Jun-02-10|| ||YouRang: I was way off base. :-(
I thought I was being clever to see 26...Re3!!! (sarcastic exclams) with the threat of ...Rxg3+ initiating a strong Q+B attack that ultimately recovers the rook with a couple pawns better.
This threat is not averted by 27.fxe3?, because I then have 27...Qxg3+ 28.Kf1 Bg2+ 29.Ke2 Bf3+ 30.Kd2 Qd6+ 31.Kc3 Qxd1 (recover rook and winning)
Testing my idea with the computer, I see that 26...Re3 actually wasn't horrible, but not nearly as strong as I was imagining it to be, since white has 27.Kf1, leaving things fairly even.
I did actually notice the potential for the bishop & rook mating pattern with rook at h1, but for some reason, I got it in my head that the rook had to get there via the h-file, and I couldn't see how to do it. Obviously, getting there via the first rank is the winning idea.
|Jun-02-10|| ||BOSTER: Looking at the Bishop on open long diagonal you at once can see the temptation to get the square h1 by rook.
To reach h1 the Rook has two possibilities.
One way-e4-h4-h1, and another
First way goes nowhere, but second is nice.
Now we have to divert white rook from first rank. 26...Qd6 is a good bite, at the same time attacking Rd1 and Nb4.
|Jun-02-10|| ||chrisowen: Ok, the swedish variation folks. Stone the rooks read, see rows one and four. Plant 26.Qd6 mode earns languid dharma. Farewell to 15.a4 arms the queenside novelty things not seen since it appears. The knightshade drops, book worms Nb4 take. Qc5 men at arms cover white's world and piece down puts him for rest.|
|Jun-02-10|| ||MaczynskiPratten: Nice puzzle. It's easy to spot a queen fork where it hits the rook on the diagonal and the knight on the file, but not so simple the other way round. Instinctively we just dismiss moves automatically where we apparently lose our Queen! Got it after a bit ....|
|Jun-02-10|| ||Chessforeva: 3D slider: http://chessforeva.appspot.com/C0_s...|
|Jun-02-10|| ||ROO.BOOKAROO: The theme is, like that of a previous puzzle, DEFLECTION, or DIVERSION, or DISTRACTION. Black has an immediate potential mate threat, with the e4 rook going to e1 then to h1, supported by the diagonal control by the b7 bishop. The only piece guarding e1 is the white rook on d1. So the puzzle boils down to how is it possible to deflect, or divert the white rook from guarding the vital square e1. This must be a forcing deflection, and the only one available is to threaten the white d1 rook with the Black queen moving to the same file on d6. This has the side advantage of preventing the potential white threat of White queen moving to its own vital square on d8 for a mate of its own.
The rest of the game follows naturally. Taking the white knight if the white rook refuses to take the black queen and moves away on the first rank.
This is the way to think of DEFLECTION. Is there an immediate mate threat? Which opponent's piece guards the vital square preventing the mate threat from developing? Is there a way to entice this opponent's piece away from controlling the vital square. This could be the theme of this week's puzzles.|
|Jun-02-10|| ||thegoodanarchist: Loved it! White fearlessly moves his rook to the d-file, only to be chased back with his tail between his legs after the cute move ...Qd6!|
|Jun-02-10|| ||jmi: This one took me ages to find. I keep thinking of trying to use the long diagonal and force mate but couldn't work it out.|
I then look at the White king's position and then realise that the White rook can never leave the back rank else it's forced mate.
Once I got that idea, I just followed the axiom of "loose pieces drop off" and Qd6 came up immediately.
|Jun-02-10|| ||MrMelad: I missed a wendsday! Very pretty and seems very easy in retrospect.|
|Jun-02-10|| ||Scarecrow: Looked at it in the morning, did not get it. Now returning at midnight, all the pieces fall into place. Little wonders of life|
|Jun-02-10|| ||Brandon plays: I missed it. I kept on trying to find a checkmate idea, but nothing was working.|
|Jun-02-10|| ||cjgone: I looked at the position and noticed how boxed up white's king is.. The bishop's diagonal allows black to checkmate white if he can get pieces on the back rank. White's rook is a main threat to getting to the back rank, but if it leaves it's a checkmate. The queen can be used to break the rook's line and bait the opponent to the checkmate. If white doesn't take, it's a free knight.|
|Jun-02-10|| ||DarthStapler: Got it|
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