< Earlier Kibitzing · PAGE 3 OF 3 ·
|Mar-19-09|| ||kevin86: A VERY easy puzzle. White is almost FORCED to make the winning move 25♖xg6 is needed to avoid losing the exchange. With the two heavy pieces and two bishops on the prowl,this game virtually wins itself.|
|Mar-19-09|| ||actinia: <johnlspouge>
your analysis runs:
28.Bxf5 Qxf5 29.Rxg7+
29…Kf8 [Rxg7 30.Qxf5] 30.Rg8+
but what if 28. ... Rxf5 instead?
|Mar-19-09|| ||mworld: first move very easy - blunder checking the first move, very difficult.|
|Mar-19-09|| ||zb2cr: As others have noted, White's tripled heavy pieces are a very strong hint that 25. Rxg6 is the first move. After 25. ... hxg6; 26. Qxg6, I analyzed 26. ... Nxf4; 27. Qh6+. My idea was initially just to remove the White Queen from being <en prise>. After 27. ... Kg8, the Black Bishop is still pinned (by the Rook) and White could snap up the Black Knight on f4 and have 2 Pawns for the exchange. Then I looked again and saw that 28. Rxg7+, Rxg7; 29. Qxg7# mates.|
26. ... Nf6, as played in the game, seemed weak to me, precisely because it blocked the Rook's protection of the Black KBP and thus made 27. Bxf5 feasible.
|Mar-19-09|| ||YouRang: Aarg! I can't believe that I didn't see 27.Bxf5!
Bad week. :-(
|Mar-19-09|| ||actinia: I agree with <grinch>|
we have not yet solved this puzzle
|Mar-19-09|| ||CHESSTTCAMPS: This position is similar to yesterday's, where all major pieces are pointed at one target and it's clear that a brute force demolition of the pawn shelter around the king is planned. However, in this situation, black has more defenders available and more defensive options, so each option must be investigated carefully.|
25. Rxg6! and now
A. 25...Bxd4 26.Rg8+ and mate next
B. 25...Nxf4 26.Rxg7 ("windmill") Nxg2 27.R7xg2+ Qe5 (or Rg7 28.Rxg7 h5 29.Rxb7+ and black must interpose the queen anyway to delay mate) 28.fxe5 and black can resign
C 25...hxg6 26.Qxg6 and now:
C.1 26...Bxd4 27.Qh6+ Rh7 28.Qxf8#
C.2 26...Nxf4 27.Qh6+ Kg8 28.Rxg7+ Rxg7 29.Qxg7#
C.3 26...Nf6 27.Bxf5 (Every attacker is used and the threat is Bxf6) Kg8 28.Bxf6 Rxf6 29.Qxf6 and there's no good defense to the threat of 30.Be6+ Kh7 31.Qh4+ Bh6 32.Rg5! followed by Bf5+.
C.4 26...Qd2 27.Qxh5+ Kg8 28.Bxg7 (28.Bxf5? Rxf5 and 28.Qh6 Rff7 seems to hold and 28.Qg5 Qxd3 29.bxg7 Qxf3+ 30.Rg2 Qf1+ is a draw) Rxg7 29.Rxg7+ Kxg7
I can't seem to find a win here for white, for instance 30.Qg5+ Kh8 31.Qh6+ Kg8 32.Bxf5 (not 32.Qg6+ Kh8 33.Bxf5?? Qe1+ followed by Rg8) Qe1+ and white can't stop a perpetual check.
I think I'm stuck here. Time to post and see what happened.
|Mar-19-09|| ||CHESSTTCAMPS: I found the game continuation easily enough, but does anyone see the win after 25.Rxg6 h7xg6 26.Qxg6 Qd2? |
click for larger view
I haven't run this through an engine yet, so I'm curious if anyone can see something I'm missing. Please review my initial post first to see the tries I considered.
|Mar-19-09|| ||Once: <grinch: i cannot see an easy win after 26. ... Rff7 27. Qxh5 Kg8.>|
I am not surprised! You have jumped the white queen from g2 to h5.
This is what Fritz makes of 26...Rff7 27. Rg5 Qa8 28. Bc3 Nxf4 29. Rxg7 Rxg7 30. Bxg7+ Kg8 31. Qg5 Nh3 32. Qg3 Nf2+ 33. Qxf2 Rxg7 34. Rxg7+ Kxg7 35. Qd4+ White is a safe piece up and dominates the centre.
The problem with 36...Rff7 is that it introduces an additional pin on the Bg7. Not only is the bishop pinned against the black king, but it is also pinned against mate on the g8 square (since the f rook has moved off the back rank).
|Mar-19-09|| ||johnlspouge: < <actinia> wrote: <johnlspouge> your analysis runs:|
28.Bxf5 Qxf5 29.Rxg7+
29…Kf8 [Rxg7 30.Qxf5] 30.Rg8+
but what if 28. ... Rxf5 instead? >
You are right: there is a problem. I generally post without editing up to Wednesday, but if I am diffident that I have a complete solution, I turn to Toga II 1.3.1. I edit, because I do not want to burden people with excess drivel, but I always indicate editing with <>. Today, Toga gave a better variation than I did, but I did not have time to analyze the variation before going out the door this morning. I was a little too excited that Toga showed the hook-and-ladder trick, which I thought would be interesting.
< <actinia> wrote: I agree with <grinch> we have not yet solved this puzzle >
I thought statements that all variations were covered were greatly exaggerated as well.
Thanks for pointing out my error. I keep a corrected version of my posts at home, so you have made my life a little easier.
|Mar-19-09|| ||dzechiel: <hms123: <Dzechiel> In your line <25...Nxf4 26. Rxg7 Nxg2> why not <27. R7xg2+>?>|
I did consider this line (it was part of my text for quite a while as I typed it up), but it looked to me like black could play 27...Rg7 then after 28 Bxg7+ Kg8 the black king would start running.
In retrospect, I see that white could play 28 Rxg7 and the mate seems unavoidable. 27 R7xg2+ is the better move, I should have looked at it harder. Thanks for pointing this out.
|Mar-19-09|| ||Once: <CHESSTTCAMPS> With my superhuman analytical ability, I can spot at a glance that 26...Qd2 leads to a mate in 14 ...|
25. Rxg6 hxg6 26. Qxg6 Qd2 27. Qxh5+ Kg8 28. Bxf5 Qxd4 29. Bh7+ Kh8 30. Bg6+ Bh6 31. Qxh6+ Kg8 32. Bh7+ Kf7 33. Re1 Qe5 34. fxe5 d5 35. Bg6+ Kg8 36. Rg1 Rg7 37.Bh7+ Kf7 38. Rxg7+ Ke8 39. Qe6+ Kd8 40. Qd7#
In other words, I fired up Fritz to find the answer!
|Mar-19-09|| ||Pawnage: <Kevin86> is right, the game pretty much wins itself. But finding <all> the follow-up moves and possibilities by just staring at the board is beyond me.|
|Mar-19-09|| ||fm avari viraf: In such positions, where White has piled up all his major forces on the g-file & where Black's castle looks vulnerable, the only move that comes to my mind is 25.Rxg6 since 25...Bxd4 is suicidal because of the back rank mate. Hence, Black has two unfavourable choices, 25...Nxf4 & ...hxg6 each one of them leading to gallows. Let's see after 25...Nxf4 then 26.Rxg7! Nxg2 then 27.Rxc7+ wins and 25...hxg6 then 26.Qxg6 & Black is defenceless. If 26...Bxd4? 27.Qh6+ Rh7 28.Qxf8# 7 if 26...Nf6 then 27.Bxf5 & again Black cannot parry the threat of 28.Bxf6 leading to mate.|
|Mar-19-09|| ||agb2002: White is a pawn up and has the bishop pair but Black is threatening 25... Bxd4, 25... Nxg3+ and 25... Nxf4. A possible solution would be 25.Bxg7+ Rxg7 26.Rg5 Nxf4 27.Qf1 but White would probably end up worse. Therefore, 25.Rxg6:|
A) 25... hxg6 26.Qxg6
A.1) 26... Nxf4 27.Qh6+ Kg8 28.Rxg7+ Rxg7 29.Qxg7#.
A.2) 26... Bxd4 27.Qh6+ Rh7 28.Qxf8#.
A.3) 26... Ng3+ 27.Rxg3 Qe1+ (27... Bxd4 28.Qh6+ Rh7 29.Qxf8#) 28.Rg1 Qe7 (28... Qxg1 29.Bxg1 ) 29.Qh6+ Kg8 30.Rxg7+ Qxg7 31.Bxg7 Rxg7 32.Qe6+ followed by 33.Bxf5 .
A.4) 26... Qa8 27.Qxh5+ Kg8 28.Bxf5 (threatens 29.Qh7+, 29.Bh7+, 29.Be6+, etc.).
A.5) 26... Qd2 27.Qxh5+ Kg8 28.Bxf5
A.5.a) 28... Qxd4 29.Bh7+ Kh8 30.Bg6+ Bh6 (30... Kg8 31.Qh7#) 31.Qxh6+ Kg8 32.Be4+ (32.Bf5+ Qxg1+ 33.Kxg1 Rxf5 34.Qe6+ (34.Qg6+ Rg7 ) Rcf7) Kf7 33.Qh7+ and 34.Qxc7 .
A.6.b) 28... Rxf5 29.Qe8+
A.6.b.i) 29... Kh7 30.Qg6+ Kg8 (30... Kh8 31.Bxg7+ Kg8 32.Bc3+) 31.Bxg7 .
A.6.b.ii) 29... Rf8 30.Qe6+ Kh7 (30... Kh8 31.Qh6+ Kg8 32.Rxg7+ Rxg7 33.Qxg7#) 31.Qg6+ Kg8 (31... Kh8 32.Qh6+, etc.) 32.Bxg7 .
A.6) 26... Rff7 27.Qxh5+ Kg8 28.b4
A.6.a) 28... Qxa3 29.Bxg7 Rxg7 30.Qe8+ Kh7 31.Bxf5+ Kh6 32.Qh8+ Rh7 33.Qf6+ Kh5 34.Qg5#.
A.6.b) 28... Qa8 29.Bxf5 and White should win.
B) 25... Bxd4 26.Rg8+ Rxg8 27.Qxg8#.
C) 25... Nxf4 26.Rxg7 Nxg2 27.R7xg2+ Rg7 (27... Qe5 28.fxe5 ) 28.Rxg7 .
D) 25... Ng3+ 26.R6xg3 Bxd4 27.Rg8+ and mate next.
E) 25... Rff7 26.Rxd6 Qa8 (26... Nxf4 27.Rd8+ Rf8 28.Rxf8#) 27.Qg5 (threatens 28.Rd8+ and 28.Qxh5).
It has been a lot of work and I'm not completely satisfied (line A.6.b) but it's time to post, check and have dinner.
|Mar-19-09|| ||agb2002: I saw 26... Nf6 and thought that 27.Bxf5 would win easily so I moved to 26... Qd2 and 26... Rff7 and got so involved with them that I forgot to include it in my post. I also overlooked 25... Rg8 but probably 26.Rg5 is enough to win.|
Hmm... from now on, I'll write down all reasonable replys before analyzing them.
|Mar-19-09|| ||johnlspouge: This puzzle displays an interesting phenomenon: on one hand, the game defense 26...Nf6 is best play according to Toga, in the game theoretic sense that it maximizes the minimum gain; on the other hand, 26...Nf6 could be considered a weak defense in that a human can hardly fail to try the refutation 27.Bxf5. Other defenses such as 26...Rff7 might be much more challenging to a human.|
I am not much aggrieved I missed 26...Nf6.
|Mar-19-09|| ||johnlspouge: Hi, <actinia>. In fact, I did get the variation correct. With Toga and a little more time on my hands, the main variation in my post should go:|
Candidates (25.): Rxg6
25.Rxg6 hxg6 26.Qxg6 Rff7 27.Qxh5+ Kg8 28.Bxf5
At this point, <actinia> astutely pointed out I had left some unclear variations unfinished. Here they are:
(1) 27…Qxf5 29.Rxg7+ Kf8 [Rxg7 30.Qxf5] 30.Qxf5
The cross-pin leaves White a B+4Ps ahead. (Note: Toga gives 30.Qxf5 as an overwhelming win, but prefers 31.Rg8+ with a complicated continuation.)
(2) 27…Rxf5 29.Qe8+ Rf8 [Kh7 30.Qg6+ Kg8 31.Bxg7 and mate eventually]
30.Qe6+ Kh7 [Kh8 31.Qh6+ Kg8 32.Rxg7+ Rxg7 33.Qxg7#]
31.Qg6+ Kg8 32.Bxg7
and White hemorrhages material to prevent mate.
|Mar-19-09|| ||CHESSTTCAMPS: <Once> wrote <With my superhuman analytical ability, I can spot at a glance that 26...Qd2 leads to a mate in 14 ...
25. Rxg6 hxg6 26. Qxg6 Qd2 27. Qxh5+ Kg8 28. Bxf5 Qxd4 29. Bh7+ Kh8 30. Bg6+ Bh6 31. Qxh6+ Kg8 32. Bh7+ Kf7 33. Re1 Qe5 34. fxe5 d5 35. Bg6+ Kg8 36. Rg1 Rg7 37.Bh7+ Kf7 38. Rxg7+ Ke8 39. Qe6+ Kd8 40. Qd7#> |
Thanks for responding. Believe it or not, from the initial position, I saw the Fritz line up to white's move 32 and I assumed this was won for white. What I missed was the right continuation after 29....Rxf5:
30.Qd8+! Kh7 (or Rc8 31.Qd6+! Kh7 32.Qd6+) 31.Qg6+ Kg8 32. Bxg7! - the point I missed
Anyone who says they found the puzzle "easy" obviously hasn't put in the analytical effort. Sure it's easy to see the initial sac, but there's a lot more to it than that. Look at the initial post from <agb2002>. Now that's analytical effort - as always from agb2002.
I think this puzzle deserves 3 1/2 stars at least.
|Mar-19-09|| ||actinia: thanks <john> and <chess>|
the jig the queen does along the h5-e8 diagonal in that last line is a maneuver I'll have to remember
|Mar-19-09|| ||Silverstrike: I'm interested by white's play on the g-file; at first it appeared to be running into a brick wall but it came through eventually. Perhaps the advance of black's f pawn is to blame?|
|Mar-19-09|| ||WhiteRook48: 25. Rxg6 was unclear to me|
|Mar-19-09|| ||Dr. J: After the text <25 Rxg6 hxg6 26 Qxg6 Nf6 27 Bxf5> (threatening 28 Bxf6), I am surprised that it has gone unremarked how poor 27 ... Qa4 was. Instead after <27 ... Kg8> there is still some work to do since 28 Bxf6 Rxf6 29 Qh7+ Kf8 achieves nothing. So White must play <28 Be6+> and now:|
28 ... Rff7 29 Bxf6 Kf8 (forced) 30 Bxf7 Rxf7 31 Bxg7+ winning. This is actually Black's best. If instead:
28 ... Kh8 29 Bxf6 Rxf6 30 Qh5+! Bh6 31 Qe8+ R (or B) f8 32 Rg8+ and mates next.
|Mar-27-09|| ||patzer2: For the Thursday, March 19, 2009 puzzle solution, White's demolition with 25. Rxg6! sets up a decisive attack against the weak Black castled position.|
Here's my computer checked breakout:
<25. Rxg6!! hxg6 26. Qxg6 Nf6>
If 26... Kg8, then White wins after 27. Qxh5 Rff7 28. b4 Qa8 .
<27. Bxf5 Qa4>
If 27... Rff7, then White wins with 28. Bxf6 when play might continue 28...Kg8 29. Qh7+ Kf8 30. Bxg7+ Ke7 31. Bf6+ Kxf6 32. Qh6+ Ke7 33. Qe6+ Kf8 34. Qxd6+ Rce7 35. Qh6+ Rg7 36. Qh8+ Kf7 37. Qxg7+ Ke8 38. Qg8#.
<28. Bxf6> 1-0
Black resigns in lieu of 28...Kg8 (28... Bxf6 29. Qh6+ Rh7 30. Qxf8#) 29. Be6+ Rcf7 30. Qxg7#.
|Mar-27-09|| ||patzer2: If 27...Kg8, then 28. Bxh6 Rxf6 29. Qxf6 should decide, as play might continue 29...Qc5 30. Qd8+ Kf7 31. Bg6+! Ke6 32. Re1+ Qe3 33. Rxe3+ Be5 34. f5#.|
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