|
< Earlier Kibitzing · PAGE 2 OF 2 ·
Later Kibitzing> |
| Jun-10-15 | | paavoh: At least Black is not drawing all his games as in the 2010 French championship (+0,-0,=11)... |
|
Jun-19-16
 | | An Englishman: Good Evening: I couldn't solve the position because I thought 27...Rf8 refuted the sacrifice. What did I fail to see? |
|
Jun-19-16
 | | Penguincw: I'd just like to say, Happy Father's Day.
This puzzle, I did not get. I just went for grabbing the knight on g6. However, it's a late-week puzzle, never got it. But hey, tomorrow's Monday. |
|
Jun-19-16
 | | al wazir: I think black would have done better to play 28...Qxe6, giving back the exchange: 29. Bf5 Qh6 30. Qxh6 gxh6 31. Bxc8 Rxc8 32. g3 Rc2 33. Rf2 Rc1+ 34. Kg2 Rd1. |
|
| Jun-19-16 | | centralfiles: 27...Rf8 28.Bg8!? Rxg8 <28...Qe8 Nxe6...> 29.Nxe6 Qe8 30.Nxg7 with Qf6 coming... |
|
| Jun-19-16 | | diagonalley: ...whoa... an impressive, very long sequence... one wonders just how far white had calculated when he offered the exchange sac(?) |
|
| Jun-19-16 | | centralfiles: <An Englishman> Just to explain 27...Rf8 28.Bg8 If 28.Nxe6 immiediately then 28...fxe6 Qg5+ Kd7 Qxg7+ Qe7
But after 28.Bg8 Qe8 29.Nxe6 fxe6 30.Qg5+ Kd7 31.Qxg7+
31...Qe7? 32.Bxe6+!
So black must play 31...Kc6
Now it seems like a win after 32.Rxf8 Qxf8 Qxf8 Rxf8 Bxe6 Rf4 g4 Rxe4 Bf5 and white walks the h-pawn
Though it's more likely I made some mistakes along the way... |
|
| Jun-19-16 | | AlicesKnight: Missed this one too. Who was it that pointed out how many beautiful combinations pan out simply to a won R+P endgame? |
|
| Jun-19-16 | | WorstPlayerEver: Hmm..guess I'm missing something, but I don't know why doesn't Black plays 26... Rc7. Seems defensible. |
|
| Jun-19-16 | | The Kings Domain: Nah, missed this one. I was thinking 24) Bxg6 to lessen black's defense on the kingside, give him double pawns and make him more prime for an attack. Gotta love these deep puzzles. And what a great game too. Stellar attack by Fedorchuk. |
|
Jun-19-16
 | | Once: Hmm. I saw 24. Ng5 as it seemed to be the most promising "puzzle-like" move in the position. Give up the exchange for a pawn plus the semblance of an attack. OTB I might have played it on the basis of a hunch, cos it's always more fun to be attacking. But I couldn't calculate through to a clear advantage. The thing is, neither can my friend Fritzie. After the moderately forced sequence 24. Ng5 Nf4 25. Bh7 Kf8 26. Qf4 Ke7 27. Rf1, we get to this position with black to move: 
click for larger viewWho is winning here? I'd rather be white because he seems to be having the most fun, but that exchange might yet come back to bite my derriere. This is where Dorfman goes wrong, according to Fritzie. He tries to start a counterattack with 27...Qb6, presumably thinking that he can meet 28. Nxe6 with 28...Qxe6 and in the words of the hymn, "all is safely gathered in". 
click for larger viewBut then he realises that white gets a strong attack with 29. Qg5+ Kf8 30. Bg6 and white is having way too much of the play. So black is forced into the ugly 28...fxe6 when white has both a king hunt and an extra pawn. If black had seen all this, he would have not played 27...Qb6. Why stick the queen out of play on b6 if you can't play Qxe6? Instead, black could have chosen a quieter move like 27...Kd7 or 27...Rf8. Here's the position after 27...Rf8 
click for larger viewWhite has the funky 28. Bg8 but it seems that black can hold this. After a couple of minutes analysis, Fritzie is calling this one only +0.6. So what are we left with? It's a speculative attack which doesn't seem to be conclusive with best play. It's worth playing 24. Ng5 because it gives Black enough rope to hang himself, but it should not have been the crushing attack that we saw in the game. |
|
| Jun-19-16 | | ndg2: Playing Qb6 immediately on move 24 would have been better for black than doing it some moves later. Taking the exchange enabled an attack too strong for black's defense. |
|
| Jun-19-16 | | offramp: <diagonalley: ...whoa... an impressive, very long sequence... one wonders just how far white had calculated when he offered the exchange sac(?)> I often wonder that. It is often very hard to tell.
Personally (I did not get this puzzle, BTW) I think white may have only seen as far as 26.Qxf4
click for larger view ...and thought, "I'm in no danger here, I have a pawn for the exchange and all my pieces near his king - I'll have a punt!" |
|
| Jun-19-16 | | catlover: Thanks for the analysis, <Once>. I wondered whether white's attack was winning in all the lines, and how much of the play on black's part was forced. This proves once again that a sacrifice to get an attack may not be 100% sound, but might work simply because the defender cannot find the best line to refute it. |
|
Jun-19-16
 | | patzer2: Playing through today's Sunday puzzle solution (24. Ng5!), with a difficult and tricky positional exchange sacrifice, somehow reminded me of an act I recently saw on the "America's Got Talent" TV show. The act, which can be viewed at https://www.youtube.com/watch?v=_WE..., involved a 50-year-old woman carrying her 55-year-old husband at a dangerous height on her shoulders while walking on a high wire over a parking lot. The standard warning from the show's announcer was "don't try this at home." Of course when your life isn't in mortal danger in a Chess games, it's Ok to take the risk of losing with a complicated positional exchange sacrifice. However, without the prompt this was a puzzle of "insane" difficulty, OTB I would probably have been inclined to play for risk-free equality with 24. Bxg6 fxg6 25. Ng5 Bf5 26. Nh3 = (0.00 @ 30 depth, Stockfish 180415). Playing guess-the-move with the puzzle, I got as far as 24. Ng5 Nxf4 25. Bxh7+ Kf8 26. Qxf4 Ke7  (+0.44 @ 29 depth, Stockfish 5SSE) where White has a good position for the sacrifice of a Rook for a Knight and Pawn, but no clear win. After 26...Ke7 27. Rf1, Black's decisive mistake was 27...Qb6? allowing 28. Nxe6  (+2.76 @ 31 depth, Komodo 9.3). Instead of 27...Qb6?, Black could have stayed in the fight with 27...Kd7 28. Bf5 (+0.42 @ 21 depth, deep Fritz 15) with only a slight advantage for White. One fascinating possibility would have been if, instead of 27...Qb6?, Black had played the natural 27...Rf8 (diagram below):
click for larger view Here (diagram above) White must find the strong surprise move 28. Bg8! (+0.59 @ 21 depth, Deep Fritz 15) to maintain an edge. The threat after 27...Rf8 28. Bg8! (diagram below):
click for larger viewis 29. Bxf7 to . For example, after 28...a6? White wins a piece and the game with 29. Bxf7! Bxf7 30. Nxf7 Qb6 31. Nd6! (diagram below) 
click for larger view31...Rxf4 32. Nxc8+ Ke6 33. Nxb6+ .
Of course this is speculation on the possibility of Black playing an inferior move. After the stronger continuation 27...Kd7 28. Bf5 we're back to playing a chess game as White an exchange down for a "slight advantage." Some players are comfortable with such positions. Others, might prefer equality by avoiding this tight rope walking risk with the cautious continuation 24. Bxg6 fxg6 25. Ng5 Bf5 26. Nh3 = (0.00 @ 30 depth, Stockfish 180415) mentioned above. |
|
| Jun-19-16 | | mel gibson: This game is a draw according to my computer even following the text move: 24 Ng5 |
|
Jun-19-16
| | patzer2: <offramp> After reading your assessment as to White's likely thinking in this game, I tend to agree that for a strong GM 24. Ng5! was probably a risk-free move offering winning chances if Black went wrong. However for a club players like myself, maintaining an "advantage" in a slightly favorable exchange down position is not a "risk-free" proposition. |
|
Jun-19-16
| | patzer2: <Once> (Position after 27. Rf1) <Who is winning here? I'd rather be white because he seems to be having the most fun, but that exchange might yet come back to bite my derriere.> Great, concise assessment of the risk versus reward proposition in playing the fun 24. Ng5! |
|
| Jun-19-16 | | Virgil A: Is 39.b5 better than the text? |
|
| Jun-19-16 | | YouRang: "Insane"
click for larger view
I'm with <Once> in that I successfully guessed the first move, <24.Ng5>; the exchange sac to gain an attack on the K position. However, this idea seems to suffer from being unforced. Anyway, assuming black bites with <24...Nxf4>, then I see white has <25.Bxh7+ Kf8> (looks safer than ...Kh8) <26.Qxf4>
click for larger view
Here, white has the resources to build up enormous pressure on f7 via Bg6 and Rf1; thus the black K should make a run for it: <26...Ke7>. Here is where things got foggy for me. I figured <27.Rf1>, but didn't see any clear attack after ...Kd7 or ...Rf8. Checking with the computer, it appears that I actually got the first few moves, and then black blundered with <27...Qb6?>, whereas 27...Kd7 would have kept the game well in hand. So, the whole rook-sac line was a speculative sac to create complications for black, and in this game it worked because black cracked under pressure. So arguably, it was the best move. Going back to move 24, the engine slightly prefers Ng5 to Bxg6, which seems to go nowhere. |
|
| Jun-19-16 | | Longview: This has to be a father's day gift. I got this one! It seemed clear that White had an active attack ready to spring on the Kingside and I followed my nose, as it were. I missed a couple of Black's responses, better than I would have played in defense, but the movement of White was pretty much a straight line of attacks. I must admit that I was so focused on the King capture that I missed 38. Be8 which balanced the armies except for the pawn dominance of white. |
|
Jun-19-16
 | | agb2002: The material is identical.
Black threatens 24... Nxf4.
The rook on f4 is trapped and 24.Bxg6 doesn't look very strong because c2 is now defenseless. For example, 24... hxg6 25.Ng5 Rc2 26.Qh4 Qc7 27.Qh7+ Kf8 28.Qh8+ Ke7 29.Qxg7 Rc1+ 30.Rxc1 Qxc1+ 31.Kf2 Qxf4 - +. Another option is 24.Ng5:
A) 24... Nxf4 25.Bxh7+
A.1) 25... Kf8 26.Qxf4 and I don't know whether White has enough compensation for the material. Black can try 26... Ke7. A.2) 25... Kh8 26.Qxf4 prepares Qh4 with some chances. For example, 26... f6 27.Nxe6 Rxe6 28.Qh3 followed by Bf5+ winning a pawn at least. B) 24... h6 25.Nxf7 Bxf7 (due to 26.Nxd8 and 26.Qxg6) 26.Rxf7 Kxf7 27.Qxg6+ B.1) 27... Ke7 28.Qxg7+ Ke6 29.Rf1 Rf8 30.Qxh6+ Ke7 (30... Kd7 31.Qd6+ Ke8 32.Rxf8#) 31.Qh7+ Ke6 (31... Ke8 32.Bg6+ Rf7 33.Qxf7#) 32.Bf5+ Rxf5 33.Qxf5+ Ke7 34.Qf7#. B.2) 27... Kf8 28.Rf1+ Ke7 (28... Kg8 29.Qh7#) 29.Q(R)f7#. B.3) 27... Kg8 28.Rf1 and mate in two.
C) 24... Qb6 25.Bxg6
C.1) 25... Qxb2 26.Rb1 Rc1+ 27.Rxc1 Qxc1+ 28.Rf1 wins a piece. C.2) 25... fxg6 allows White a virtual extra pawn. A nice line is 26.Nxe6 Qxb2 27.Raf1 Rxe6 28.Qf3 with the double threat 29.Rf8+ and 29.Qxd5. C.3) 25... hxg6 26.Qh4 followed by Qh7, Raf1, etc. with attack. This is all I can do today. |
|
| Jun-19-16 | | BOSTER: After white 23.Qg3 black could capture white rook playing Ng6.
So , white had to play 24.Ng5 to release his rook.
This is why I'd not say that this was the classical sacr. |
|
Jun-19-16
 | | scormus: <Once> nice analysis and assessment. I thought as I played it through that 27 ... Qb6 was the wrong way to go, it was the sort of tempting move that I play when the game seems to be slipping away and I feel the need to do something positive. But I just get into more trouble. ... Kd7 and he might have been able to hold it. |
|
| Jun-19-16 | | RandomVisitor: Ater 27...Kd7
click for larger viewKomodo-10-64bit:
<+0.00/45 28.Bf5> Qe7 29.Qg4 Rf8 30.Nh7 Rg8 31.h3 Rce8 32.Bxe6+ fxe6 33.b3 a6 34.Kh2 Kc8 35.Ng5 Qd7 36.Rf7 Qc6 37.b4 Kb8 38.a4 Ka7 39.b5 axb5 40.axb5 Qb6 41.Rd7 Qxb5 42.Rd6 Rgf8 43.Nxe6 Rf1 44.Nc5 Qb1 45.Qe2 Rh8 46.Rd7 Rh1+ 47.Kg3 Qg6+ 48.Qg4 Qc2 49.Rxb7+ Ka8 50.Rb3 Qc1 51.Qf3 Qg5+ 52.Qg4 Qc1 |
|
 |
|
< Earlier Kibitzing · PAGE 2 OF 2 ·
Later Kibitzing> |
Kibitzing
sac: 24.Ng5