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|Jun-27-08|| ||SuperPatzer77: <patzer2> <If 24. axb3, then, due to the decoy of the a2 pawn and subsequent clearance of the a-file, Black has mate-in-three after 24...Qa1+ 25. Kc2 Qb2+ 26. Kxb1 Qa1#.>|
<patzer2> You must have made a typing error in algebraic notation - 25...Qb2+, 26 Kxb1 (????)
Correct algebraic notation is 24. axb3 Qa1+, 25. Kc2 Qb2+, 26. Kd3 Qc3#
|Jun-27-08|| ||patzer2: <SuperPatzer77> Thanks for the correction. I'll delete and repost.|
|Jun-27-08|| ||patzer2: For all practical considerations, today's Friday puzzle solution initiates a mating attack which begins with the decoy (sham) sacrifice 22...Re2!|
Here's my breakout:
<22...Re2!! 23. Qxe2>
White is practically forced forced to capture the Rook. Otherwise he falls victim to a quicker mate or obvious loss of decisive material.
If White tries to avoid immediate capture or exchange of material, one quick mate possibility is 23. Qd3 (23. Qc1 Qxa2#) Qxa2+ 24. Kc1 Qb2#.
White can delay the inevitable mate by giving up decisive material with 22...Re2! 23. Rd2 Rxd2 24. Ra4 Qxa4 25. Qxd2 Qxh4 . However, this and other such losing possibilities are a direct result of the primary mate threat(s) in the game continuation.
This follow-up (pseudo) sacrifice is the key to the combination, as it forces mate-in-four moves or less. Note that the move contains elements of three tactical themes: deflection (if the King moves); decoy ( if the Rook is captured); and clearance (as the capture of the Rook clears the a-file for a winning queen check on a1).
If 24. axb3, then, due to the decoy of the a2 pawn and subsequent clearance of the a-file, Black has mate-in-three after 24...Qa1+ 25. Kc2 Qb2+ 26. Kd3 Qc3#.
If 24. Kc2, then this deflection of the King results in mate-in-one with 24...Qc3#.
If 24. Qb2, then it's mate-in-three after 24...Rxb2+ 25. Kc1 Qc3+ 26. Bc2 Qxc2#.
This initiates a mate-in-three ( or follows up on the mate-in-four begun with 23...Rxb3!).
White resigned in lieu of 25. Qc2 (25. Bc2 meets the same fate) 25...Rb1+! (note how this move combines the decoy and pin tactics to force White's King to the b1 square) 26. Kxb1 Qa1#.
|Jun-27-08|| ||zooter: am I the only one today who didn't get it? (I got Re2, but missed the followup instead option for Qc3)|
Wow, must be a record of some sort
|Jun-27-08|| ||patzer2: White's most obvious losing move was 22. Rg4?
Instead, 22. Rdf1 avoids the immediate mating combination and holds out some hope of a draw in an inferior position.
Earlier perhaps White could have improved with 5. e4 as in Gelfand vs M Gurevich, 2005, or 10. Nxd4 as in G Johnsen vs A Esbensen, 2006, or 14. Bf5=.
|Jun-27-08|| ||kinggambits: I have one comment on this puzzle. It signfies the importance of retro-analysis not only in chess but also elsewhere in other strategic decision making.|
In this puzzle it is easy to see the Qa1# and then look at Rxb3 and finally arriving at Re2. Ofcourse all the lines are difficult to see immediately.
In an over the board situation, the idea would be to look at possible mates (or material gain) and work backwards.That is first looking at what is preventing the final outcome and how to overcome it. etc
As in this case by deflecting the obstacle, Queen protecting the b3 square in this puzzle.
|Jun-27-08|| ||kevin86: I answered this one-but alas,it seems that it was too easy for a Friday puzzle.|
Again a mate in three at the end:
24...♕c3+ 25 ♕c2 or ♗c2 ♖b1+ 26 ♔xb1 ♕a1#.
It looks like another Epaulette clone.
|Jun-27-08|| ||ajk68: What is the response to 24. Ra4
|Jun-27-08|| ||SuperPatzer77: <ajk68> <What is the response of 24. Ra4?> You mean that it is 23. Ra4 - not 24. Ra4. |
22...Re2!!, 23. Ra4 Qxa4!, 24. Qxe2 Rxb3+!, 25. axb3 Qa1+, 26. Kc2 Qb2+, 27. Kd3 Qc3#
After 24...Rxb3+!!, 25 Kc1 (instead of 25 axb3) Qa3+, 26. Kd2 Qb4+, 27. Kc1 (27. Kc2 Qc3#) Qc3+, 28. Qc2 (or 28. Bc2) Rb1+!, 29. Kxb1 Qa1#
|Jun-27-08|| ||swordfish: I finally got a Friday puzzle! Hope it wasn't too easy.|
|Jun-27-08|| ||messachess: Easy Easy|
|Jun-27-08|| ||bakuazer: very easy, i am surprised. I saw the first move in about 30-40 seconds. and by that time i already knew what follows the first move. easy for friday.|
|Jun-27-08|| ||Magic Castle: What makes this puzzle difficult is the brilliant 24...Qc3+. In fact even after this key move was revealed, it took me time to realize the forced moves sequence 25. Qc2..Rb1+ 26. Kbi...Qai#. These are easily missable since 24....Qa3+ is more obvious (snaring the queen next move) for average players like me.|
|Jun-27-08|| ||messachess: For managers of this feature on this site to find problems in increasing degree of difficulty comparable in difficulty to other days of the week problems, has got to be some work--maybe a lot of work.|
|Jun-27-08|| ||johnlspouge: Friday (Difficult): Black to play and win.
Material: Even, with Bs of opposite color. Both sides have strong attacks against the K, with the White Bf5 and Rg5 about as well placed as the Black Bf6 and Rb1. The White Nd6 is more aggressively placed than its Black counterpart Nf8, but in compensation the Black Qa4 and Re7 have more aggressive potential than the White Qc2 and Rd1.
Candidates (22…): Re2
22…Re2 (threatening 23…Rxc2 and 23…Qxa2+ 24…Qb2#)
Counterattack (23.Bh7+ or 23.Rxg7+) or refusal of the sacrifice is infeasible, so the sacrifice 22…Re2 must be accepted, deflecting Qc2 from protection of Pb3.
The second sacrifice 23…Rxb3+ cannot be refused.
(1) 24.Kc1 [Kc2 Qc3#] Qa3+ (threatening 25…Qb2#)
25.Kd2 Qb4+ 26.Kc1 [else Qc3#] Rb1+ 27.Kc2 Qb2+ 28.Kd3 Qc3#
Acceptance of the sacrifice also leads to mate.
(2) 24.axb3 Qa1+ 25.Kc2 Qb2+ 26.Kd3 Qc3#.
|Jun-27-08|| ||Kasputin: A full-blown middlegame - material is even with lots of pieces in play. White has a knight deep into enemy territory, a rook on the g file, along with other pieces that look (initially at least) well placed. Black also has aggressively posted pieces, and one of the first things I notice is the black bishop on the a1 h8 diag. and the black queen that wants to land on a1 if given the chance.|
There seems to be two candidate moves for black, both with the goal of getting past white's protective a and b pawns and opening up the white king position for the queen to enter:
22 ... Rxb3+
22 ... Re2
At first glance ...Rxb3 doesn't look too promising after the white queen captures the rook on b3. ...Re2 looks like it might divert the queen away b3 and appears to merit investigation first. Here's how the most straightforward line (to me) looks:
22 ... Re2
23. Qxe2 Rxb3+
24. axb3 Qa1+
25. Kc2 Qb2+
26. Kd3 Qc3#
But this isn't all forced. So how can white deviate and what happens then?
22 ... Re2
What if white doesn't take the rook? If the white queen stays on the 2nd rank, then the queen simply gets captured - same with moving Qc3 or Qc4. And if the 23. Qc4 then even better then capturing the white queen is ...Qxa2+; 24. Kc1 Qb2#
Moving 23. Qc1 allows ...Qxa2# Moving 23. Qd3 (or even Qe4) allows ...Qxa2+ 24. Kc1 Qb2#
So clearly after 22 ... Re2 the queen can't do anything to stave off loss. But what about playing 23. Bh7+ or Rxg7+ or even Nxf7?
23. Bh7+ Nxh7 [23 ... Kh8?? and 24. Nxf7#]
Moving the bishop to h7 doesn't change any of the previous "what can the white queen do" analysis, so white has to either lose as before or play:
24. Rxg7+ Bxg7
In the previous analysis, the black bishop was needed only as support for the entry of the black queen along a1-h8. So once again nothing has changed (except that white plays some extra moves and loses more material). For example, playing 25. Rg1 pins the bishop but this pin is meaningless. Black just plays ... Rxc2 and wins.
23. Rxg7+ Bxg7
And now the same thing. White can check with the bishop, which transposes into a1) above and once again doing anything with the queen won't work. Moving the remaining rook over to g1 simply allows black to capture the white queen. Finally:
Why complicate things by taking the knight? Black should capture the queen and go from there.
(I am going to split my posting here because I have a feeling it is too large to post at this point).
|Jun-27-08|| ||Kasputin: ...Continued from previous post
Is there anything else after 22 ... Re2? Well 23. Nb7 (threatening the black queen) looks insufficient after ...Rxb7. Alternatively 23. Nc4 dxc4 and I can't see that white gains anything by losing the knight. Another knight alternative is to play 23. Ne8.
This is interesting - playing 23. Ne8. Should black take the knight or just go ahead and take the queen? 23 ... Rxc2; 24. Rxg7+ Bxg7 and black looks okay. Instead 24. Nxf6+ Kh8; 25. Rxg8 Qxa2# and white is too late with the king-side attack. Alternatively 24. Nxf6+ Kh8; 25. Kxc2 Qxa2+. Again it looks like black is okay. But this line does look like it has some dangers. If 23. Ne8 really were played, it might be safer to play ...R(b)xe8. That way the rooks are doubled on e-file and white has lost the knight. But I think I've looked at this enough to say that black should win with careful play.
There is one last move that white can try after 22 ... Re2 and that is 23. Rd2. But then after ...Rxd2 it looks like white is sunk once more.
So unless I missed something white can either try a swindle or just take the white rook:
23. Qxe2 Rxb3+
As mentioned initially, taking the rook with the a pawn doesn't work. Instead moving 24. Kc2 allows black to mate with ...Qc3#. So white can try:
24. Kc1 Qc3+
25. Qc2 Rb1+
26. Kxb1 Qa1+#
A nice finish, which wasn't initially very easy for me to see.
There is a lot going on here and after getting the first 2 key moves in yesterday's puzzle's but missing a fairly obvious variation, I hope I am correct with this one. Let's see.
|Jun-27-08|| ||zb2cr: <zooter> plaintively wrote:|
"am I the only one today who didn't get it? (I got Re2, but missed the followup instead option for Qc3)"
Take heart, <zooter>. <openingspecialist> and <whiteshark> also confessed to missing it. Further, though I found today's puzzle, I normally am only about 50% accurate on Friday, so for me, it's a random walk.
|Jun-27-08|| ||Kasputin: It's interesting that lots of kibitzers called this "easy." I would say instead that it is deceptively easy. Trying to see a way to get the black queen to a1 makes playing 22 ... Re2 a fairly obvious candidate move. But I would suggest that white has some dangerous looking threats against the black king. I don't think they work, but I don't think they can be discounted too quickly either. I can only speak for myself, but if this were a real game situation, and I had black in this position, I would hardly characterize it as easy, and I would want to make certain, with whatever ability I might have, that my king is safe before playing 22 ... Re2.|
|Jun-27-08|| ||DarthStapler: solved it nearly except for the Kc1 lines which I solved later|
|Jun-27-08|| ||MiCrooks: I had a lot more trouble coming up with yesterdays in spite of being familiar with the theme! This one pretty much jumped out at me. I think the idea of "retro" analysis is correct...that is basically how my thought pattern went. I saw that Rxb3+ axb3 would lead to mate and then looked for a way to distract the Q. Had to consider that the Q move opened up a flight square but that easily dismissed. Then it was a matter of dealing with an immediate running of the King. It all fell together quickly.|
|Jun-27-08|| ||RandomVisitor: After 12...a6
click for larger view
1. (0.03): <13.Rde1> Bg4 14.Bd2 Qc7 15.Ne4 Ne6 16.Be3 Bxf3 17.gxf3 Nxe4 18.Bxe4 Bf6 19.Rd1 Rad8
2. (0.00): <13.Be3> Bg4 14.Ne2 b5 15.Rc1 Rc8 16.Ng3 Qd7 17.Nf5 bxc4 18.Nxe7+ Qxe7 19.Bxc4 Nd5
|Jun-27-08|| ||johnlspouge: Many kibitzers (e.g., <dzechiel>, <YouRang>, and <Once>) imagined first Qa1#, and then worked backwards from the "impossible" goal Qa1# to find 23...Rxb3+ and 22...Re2. In contrast, I looked for asymmetries in White's and Black's attacks on the K and then tried to leverage Black's superiorities into a mating combination, starting from Rxb3+ and then Re2. My pattern recognition (or unconscious calculation) indicated immediately that 22...Re2 worked, but led only to the prosaic finish 24...Qa3+ 25...Qb4+ etc. The imagination in explicitly seeing Qa1# foreshadowed the elegant (or - I like the adjective - <crisp>!) mate 24...Qc3+ 25...Rb1+ 26...Qa1#.|
I am posting my minority report, only to point out that there is usually more than one way to solve a problem.
|Jun-27-08|| ||SufferingBruin: The under 1300 checks in.
Many pieces aiming for the white king. The Bishop on the long diagonal and the rook on the b-file beg to be utilized but there's the white queen in the way.
22. ... Re2!
23. Qxe7 Rxb3
24. axb3 Qa8+
and the king has two diagonal steps before being mated.
22. Rd7 loses material since black owns the square. If the queen moves away from the rook, 23... Qxa7 leads to mate.
Time to check.
(UPDATE: I corrected a typo in this post--earlier I typed 22... Re7)
|Jun-27-08|| ||SufferingBruin: I wonder about Dovitiis move 17... Bxf3. Doesn't Bxf5 look more wise? It keeps a bishop/knight imbalance and keeps the g-file closed, what with that file leading directly to the king and all. I'm certainly not saying he made a mistake. I'm just saying that there are plenty of us who would reflixively exchange the bishops, no? |
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