< Earlier Kibitzing · PAGE 2 OF 2 ·
|Mar-15-09|| ||Kinghunt: I saw g5 and Rh3+, but couldn't find the continuation from there.|
|Mar-15-09|| ||dzechiel: White to move (20?). Black is up a knight. "Insane."|
Once again my bridge-playing pal, John Swanson, is visiting and we are looking at the diagram together. The fact that black is up a knight means that white will not win this by simply picking up a piece. Either the black queen or the black king are going down.
Even though black is up in material when you count everything, the fact that the queen-rook and queen-bishop are still on their home squares means that white is ahead during the comming skirmish.
This move has many good points, the most obvious being its forcing nature. The black queen is attacked and must respond. Black seems to be forced to choose from
Should black choose to give the queen back right away and try to maintain material equality with
20...Nxd4 21 gxh6 Nxb3
white ignores the kngiht and continues with
with the dual threats of 23 gxf8=Q+ and 23 Qh5+ Kg8 24 Qh8#.
That's no good. On
on the queen and indirectly on g7. I can't believe that this is good for black in any scenario. This can't be best.
black does now threaten 21...Qxd4+ which would put the brakes on white's attack. But I think white can respond
and the black queen finds herself again on the run, somewhere along the fourth rank. Let's say
22 Rh3+ Kg8 23 Qh5
and it's all over. 22...Kg6 23 Qh5+ Kf5 is no better.
So, it comes down to trying
White should now take advantage of the available h-file.
21 Rh3+ Kg8
It seems here that white can follow up with
threatening to play 23 Qh4 and 24 Qh8#. This is too easy for an "insane" position. So what has been overlooked?
Time to check and find out.
I looked at 22...gxf6 but was planning to respond with 23 exf6, covering g7 and denying the black queen that square. Can anyone with good software verify if that still wins? Thanks.
|Mar-15-09|| ||Manic: <dzechiel>
You did well but 23.exf6 loses to 23...e5 I think.
|Mar-15-09|| ||andymac: <Manic>, <dzechiel>: 23. exf6 e5 24. Qh4 wins for White, I think?|
|Mar-15-09|| ||dzechiel: <Manic: <dzechiel> You did well but 23.exf6 loses to 23...e5 I think.>|
You are quite correct! I should have kept quiet. ;)
|Mar-15-09|| ||patzer2: For today's Sunday puzzle solution, Bologan's 20. g5!! initiates a decisive attack on Black's helpless King position.|
I found Bologan's followup moves and his annotations more than sufficient to demonstrate White's winning possibilities.
|Mar-15-09|| ||goodevans: After last week's slightly disappointing Sunday, this was back to Sunday insanity at its best!|
|Mar-15-09|| ||apoka: That puzzle was quite hard. I analysed two moves in detail (as good as possible without moving pieces) from seven candidate moves (fxg7, g5, Rff3, Qd3, Be3, Bc5, Kg2):|
The first analysed move is 20. Rff3. The reply 20...Nxd4 can be met with Rh3. If White continues to capture with 21...Nxb3, we bring the Queen into play with 22. Qd3. After analysing some variants, I concluded that this is winning for White. As another reply to 20. Rff3, I also took Qg6 into account. After, Rh3+ Kg8 we play Rh5 which is also winning for White after some analysis. However, the key defense move for Black is the calm 20...Kg8. I see no reasonable reply as 21. Rh3 can be met with Qf4. In this line, White cannot double rooks on the h file and d4 is under attack (Bc5 is possible, but then e5 is no longer defended and White has a slight advantage). Overall, this very nice rook lift just fails to a simple defense move.
The other move I considered is g5. I spend quite some time to verify that Black cannot capture the pawn. (It looks wrong to take the pawn, but actually verifying this was not that easy for me.) I tried Qg6 as defense move for Black and came up with Rh3 followed by Kg8. I did not see the powerful 22. Qg4 move, so the puzzle is not really solved, but at least the direction was correct.
|Mar-15-09|| ||njchess: I looked at this for about 30 seconds and only one move seemed to make sense. 20. g5 Qg6 21. Rh3+ Kg8 22. Qg4. This is the key move in the sequence. If Black plays Nxd4 or gxf6, he is sunk. I'll check, but I know the first move is one that Bologan would not miss.|
|Mar-15-09|| ||Utopian2020: Whenever I see the Queen in front of the King, my mouth begins to water like Pavlov's dog hearing the dinner bell. Unfortunately, I could not see the moves to get the job done.|
|Mar-15-09|| ||patzer2: The big question for me in this game is not whether 20. g5! is a strong and winning move, but whether an earlier move (14. f5!?) was sound.|
At a glance the insane (but maybe not so crazy) move is 14. f5!?, which allows 14...Bc5 with a pin that initially appears to leave Black up a piece and White without a clear winning continuation. In looking at the Opening Explorer from this 2004 game, I see it's the only time the move was played in our OE database. The only other game where White had a chance to play the move again was later in 2007 when 14. Rf3 was tried without success in J Dworakowska vs K Spraggett, 2007
After 14. f5!?, I'm not so sure that the attempt to win a piece with 14...Bc5 is completely sound (even though it may be OK). My computer evaluations initially show Black to be winning after 14...Bc5, but they begin to slowly slip until Bologan's 20. g5! completely turns the evaluation around in White's favor.
Perhaps safer for Black is 14...Nd7, when Black seems to hold with a small but clear advantage after 14...Nd7 15. f6 gxf6 16. exf6 Bxf6 .
P.S.: Would be curious to see a Rybka 3 evaluation of 14. f5!? at 20-ply or greater on a multiple processor, as I don't have great confidence on what I'm seeing on my computer evaluations in this complicated position.
Also does anyone have a copy of this informant to see if Bologan has any commentary on Black's best play after 14. f5!?
|Mar-15-09|| ||Jimfromprovidence: I thought the position if 22…Nxd4 was very tricky to figure out.
click for larger view
In his annotations Bolognan provides a neat answer.
22...Nxd4 23.Qh4 Ne2+ 24.Kf2 Qf5+ 25.Ke1 Qxh3 26.Qxh3
In this sequence IMO it takes a lot of guts to play 23 Qh4 because white knows this move leaves his king subject to successive checks. He first has to navigate these checks precisely before he forces black to give up material.
|Mar-15-09|| ||Jimfromprovidence: Here's a sharp derivative puzzle. The position is after 22...Nxd4 23 Qxd4.|
click for larger view
Black to play. WHITE to mate in eight.
|Mar-15-09|| ||johnlspouge: Sunday (Insane):
Bologan vs P Schlosser, 2004 (20.?)
White to play and win.
Material: Down N for 2P, with Bs of opposite color in a midgame. The Black Kh7 has 3 legal moves. The Black Qg6 has 2 flight squares outside the h-file. The Black Q-side is undeveloped, so White must exploit his advantage in development, before his material deficit asserts itself. If White can protect h3: (1) the Black Kh7 and Qh6 are subject to a pin from Rb3-h3; and (2) because of the limited mobility of Qg6, Pg4 might then be indirectly protected at g5 by the sequence Rb3-g3 Qg5-h6 Rg3-h3. The White Qd1 is burdened with protecting Bd4; Rf1, with Pf6. White should, however, activate his heavy pieces to control the h-file and to discourage the Black plan Rf8-h8 Kh7-g8.
Candidates (20.): Kg2, g5
Black cannot accept the sacrifice of Pg5:
(1) 20…Qxg5+ 21.Rg3 (threatening 22.Rxg5)
22.Qg4 (threatening 23.Rh3 or 23.Qxg7+ 24.Rxg7+ 25.Rf3 26.Rh3#)
(1.2) 21…Qh4 [Qe4 is worse]
<[Here, I went for 22.Rg4, which also leads to an easy win.]>
(2) 20…Qg6 21.Rh3+ Kg8
<[Here, I went for 22.Rf4 (threatening 23.Rfh4 24.Rh8#), which also leads to an easy win.]>
<[Here, the winning move is 21.Bf2, but I went for 21.Rf4, which only gives White some pull after many complications. It is interesting that the variation most difficult to me was not even mentioned.]>
|Mar-15-09|| ||agb2002: Black is a knight ahead but his king is not very safe. Trying to pin the royalty with 20.Rff3 seems too slow: 20... Nxd4 21.Qxd4 (21.Rh3 Nxb3 22.Rxh6+ gxh6 23.axb3 Rg8) Qc1+.|
A better option is to open lines for the rooks with 20.g5:
A) 20... Qxg5+ 21.Rg3
A.1) 21... Qh6 22.fxg7 Re8 (22... Rg8 23.Qd3+ wins) 23.Rxf7 Kg8 24.Qf3 Nxd4 (or Bd7) 25.Rf8+ winning.
A.2) 21... Qh4 22.Rxg7+ Kh8 (22... Kh6 23.Be3+) 23.Rf4
A.2.a) 23... Qxf4 24.Qh5+ Qh6 25.Qxh6#.
A.2.b) 23... Qh3(6) 24.Bf2 threatening 25.Rh4.
A.3) 21... Qxg3+ 22.hxg3 .
B) 20... Qg6 21.Rh3+ Kg8 22.Rf4 (threatening Rfh4 and Rh8#)
B.1) 22... Qxg5+ 23.Rg4 .
B.2) 22... Nxd4 23.Qxd4 Qxg5+ 24.Rg4 Qc1+ 25.Kg2 Qxc2+ 26.Qf2 Qxf2+ 27.Kxf2 g6 28.Rfh4 .
B.3) 22... gxf6 23.exf6 followed by Rfh4 or transposes to the previous lines.
C) 20... Qh4 21.Rf4
C.1) 21... Qxg5+ 22.Rg4 Qh6 (22... Qh5 23.Rxg7+ Kh6 24.Rh7+ and mate soon) 23.Rxg7+ Kh8 24.Qg4 Nxd4 25.Rh3 Ne2(f3)+ 26.Kf2 .
C.2) 21... Qxf4 22.Rh3+ Kg6 (22... Kg8 23.Be3 Qb4 –23... Qxe3 24.Rxe3 won't save the king- 24.Qh5 Qe1+ 25.Kg2 ) 23.Be3
C.2.a) 23... Qxe5 24.Qh5+ Kf5 25.Rf3+ Ke4 26.Qg4+ Qf4 27.Qxf4#.
C.2.b) 23... Qf5 24.Qh5#.
C.2.c) 23... Qe4 24.Qh5+ Kf5 25.g6#.
C.2.d) 23... Qa(b,c)4 24.Qh5+ Kf5 25.g6+ Ke4 26.Qf3+ Kxe5 27.Qg3+ and mate in two.
C.2.e) 23... Qxe3 24.Rxe3 threatening Qd3+, Rh3-Qh5, etc.
Time to post, check and have dinner.
|Mar-15-09|| ||agb2002: <johnlspouge: ...
(2) 20…Qg6 21.Rh3+ Kg8
<[Here, I went for 22.Rf4 (threatening 23.Rfh4 24.Rh8#), which also leads to an easy win.]>> I agree, although I haven't checked the line with the computer. Perhaps tomorrow.
|Mar-15-09|| ||johnlspouge: < <agb2002> wrote: [snip] C) 20... Qh4 21.Rf4 >|
It's reassuring to see you, too, went for the bloodthirsty
20...Qh4 21.Rf4 :)
Unfortunately, Toga II 1.3.1 gives
20...Qh4 21.Rf4 Qxf4 22.Rh3+ Kg8 23.Be3 Qf5
24.Qh5 Qxh3 25.Qxh3 Ne7 26.fxe7 Re8
with value 0.33 P for White.
|Mar-15-09|| ||WhiteRook48: missed the tricky attack|
|Mar-15-09|| ||CHESSTTCAMPS: I'm afraid I can't end my Sunday slump.
This position is similar to yesterday's puzzle, where black has not moved rook and bishop on one wing. The difference is that in yesterday's puzzle, material was "even", whereas here, black is a minor piece ahead. However, white's pawn on f6 is demonstrably worth at least a minor piece in some continuations. The mating combinations that are possible with a queen and advanced pawn operating against a weakened castled position are quite familiar to experienced players. If white can get rid of the annoying black queen, the only king-side defender, the white queen will have a field day.
My principle candidate was 20.R1f3 with the idea:
20.R1f3 Nxd4? 21.Rh3! Nxb3 22.Qd3+!
A useful gain of tempo to allow the queen access to h3. If now:
A. 22... g6 23.Rxh6+ Kxh6 24.Qe3+! Kh7 (24...g5 25.Qh3+ Kg6 25.Kh5#) 25.Qh3+ Kg8 26.Qh6 and mate next move.
B. 22... Kg8 (or Kh8) 23.Qh3 Kh7 24.g5 Kg6 25.Qxh6+ Kf5 26.Qxf8 Nd2 27.Qxf7 Nf3+ 28.Kf2 Nxe5 (virtually all forced to this 29.Qg7 Bd7 30.f7 Ng6 31.Qf6+ and black can resign, because the deadly f and g pawns will cost at least two pieces to stop.
So it's clear that black has no chance after 20.R1f3 Nxd4 if white continues correctly.
The analysis so far, I finished pretty quickly. Then I got stuck. Black has been far too cooperative by swapping off white's bishop and allowing the win of his queen. My recent misses have happened because I failed to consider the best defensive candidate. What about other candidates such as 20...Qg6?
At first I didn't see a convincing continuation and I was ready to give up on 20.R1f3. I started to investigate the alternative candidate 20.fxg7 (with the idea of getting a rook to f6), but I didn't get anywhere. Then I came back to 20.R1c3 and I saw the potential of 20...Qg6 21.Rh3+ Kg8 22.g5!, a possibility that had crossed my mind earlier.
Examining the alternative defensive candidates in turn:
C. 20...Qg6 21.Rh3+ Kg8 22.g5
The threat is 23.Qh5! Qxh5 24.Rxh5 Nxd4 25.R3h3 and black can't stop mate. So now:
C.1 22...Qxg5+ 23.Rbg3 Qxg3+ (23..Qxd4+ 24.Qxd4 Nxd4 25.Rxg7#) 24.hxg3 Nxd4 (or ...g6 25.Qd2 followed by Qh6) 25.Qxd4 and it's obvious there no defense against a quick mate.
C.2 22... Qe4 23.Qh5! Qe1+ (25... Qxd4+ 24.Rbe3! and black can delay but not stop mate) 24.Kg2 Qd2+ 25.Bf2 Qe4+ 26.Rbc3 and black is out of useful checks.
C.3 22... Nxd4! 23.Qxd4 Qxg5+ 24.Rhg3 (to keep the b-rook to defend checks at b1) Qc1+ 25.Kg2 Qxc2+ 26.Qf2 Qe4+ (... Qxf2+? 27.Kxf2 g6 28.Rg4 Bd7 29.Rh3 Rac8 30.Rgh4 and black has a few checks but can't stop mate on h8) 27.Kg1 stops the checks, but I still can't find a clear win after 27...g6.
I think I'll throw in the towel - I suspect the right move is an immediate 20.g5, but my brain is too numb to work it out.
A challenging and interesting set of puzzles this week.
|Mar-15-09|| ||stukkenjager: 20.g5 Qg6
[20... Qh4 21. Bf2! Qxg5+ 22.Rg3)
20... Qxg5+ 21. Rg3!)]
21. Rh3+ Kg8 22.Qg4!! checkmate coming up, crushing!
|Mar-15-09|| ||CHESSTTCAMPS: <<agb2002> Black is a knight ahead but his king is not very safe. Trying to pin the royalty with 20.Rff3 seems too slow: 20... Nxd4 21.Qxd4 (21.Rh3 Nxb3 22.Rxh6+ gxh6 23.axb3 Rg8) Qc1+.>|
In your parenthesized note, I believe that the finesse 22.Qd3+! (instead of 22.Rxh6+) wins for white. However, I believe that your general assessment (that it's too slow) is correct. Against the defense 20.... Qg6 it seems to lose a tempo versus the text. See my initial post.
|Mar-15-09|| ||zb2cr: I'm sort of in the same boat as <dzechiel>; I found 20. g5, Qg6; 21. Rh3+, Kg8; 22. Qg4, but I thought 22. ... exf6 won. As <Manic> points out, this is not true.|
|Mar-15-09|| ||outplayer: An open file has a great worth. I saw 20.g5 but I didn't came up with Bologan's plan of occupying the h-file. In the final position all his major pieces have been placed there.|
|Mar-15-09|| ||outplayer: Sorry. I should have said "I didn't come up..."|
|Dec-14-10|| ||mastermind7994: To what it was threatened as a mate it trapped the queen. Very nice indeed.|
< Earlier Kibitzing · PAGE 2 OF 2 ·