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< Earlier Kibitzing · PAGE 2 OF 2 ·
Later Kibitzing> |
| Jun-01-16 | | Cybe: 25... b5! and Black is more or less safe (however this defense is easy for the strong engine). |
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| Jun-01-16 | | Geronimo: White's dark-squared bishop was the key to figuring this one out, even though I'll admit I didn't calculate through to the last text move. The knight at f6 is causing complications for white, but also defending the weakened king from the bishop's death ray on the long diagonal. So white's rook sacrifice removes all obstacles, and with the queen now free to move about the knight must also inevitably fall (no longer mattering if black retakes f6 with the bishop or rook. The queen can finally sweep in where she will. Fun puzzle, and I'm 3 for 3 this week! |
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| Jun-01-16 | | leRevenant: Gad ! Seems difficult for a medium easy. |
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| Jun-01-16 | | diagonalley: i found this hard for a wednesday :-( |
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| Jun-01-16 | | cocker: Nowhere near 'medium/easy'. You can do better than this <CG>. |
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| Jun-01-16 | | gofer: I "saw" <26 Rxf5>, but I didn't believe it worked. I thought that <26 ... Bf8 27 Qg5 h6 > was a problem for white. 
click for larger viewI am still not sure what happens...
28 Bxf6 Rxf6
29 Qxf6 gxf5
click for larger view28 Qg3 Bg7
click for larger view28 Rxh6 Bxh6
29 Qxh6 gxf5
click for larger viewWhat do our silicon friends calculate after <26 ... Bf8 27 Qg5 h6 >? |
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| Jun-01-16 | | amitjoshi79: After 27 h6? I think Bf6 |
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| Jun-01-16 | | saturn2: I stared at this one rather long and settled for Rxf5 followed by the queen check Qg5. My idea behind this was to play Rh6 afterwards and thereby regain a piece on f6, and later attack the king with d4 Bd3. Complicated? |
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Jun-01-16
 | | gawain: So 25...Be7 was the losing move. We can understand that Black wanted to get the bishop to f8, but White acted too quickly! Black is seemingly OK after such moves as 25...Qb8 or 25...Bd5. |
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| Jun-01-16 | | schachfuchs: I quickly found 26.Rxf5 gxf5(?) 27.Qg5+ Kh8 (27...Kf8 28.Rxh7) 28.Qxf5 (threatening Qxh7#), and also the 'execution' Kg8 29.Qg5+ Kh8 (29...Kf8 30.Rxh7) 30.Rg4 with mate on g7 or g8.
So, I was pretty sure black would not accept the Rf5 and try to find a better defence. However, I settled with 26...Bf8 27.Qg5 threatening Rxf6. Is that enough for full points?! |
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| Jun-01-16 | | TorontoNewf: <gofer>
26 ... Bf8 27 Qf4 seems to open up other doors.
27 ... gxf5 28 Qg5 Bg7 29 Rh6 piles up on f6
To early in the morning for me - there will be blood at f6. Is f6 defensible? |
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| Jun-01-16 | | Once: Another slightly weird POTD. The line after 26. Rxf5 gxf5 27. Qg5+ is probably around a Wednesday level. But 26...gxf5 isn't forced. Instead, black could defend his weak g7 square with 26...Bf8. He could open up the seventh rank for his queen to help in the defence with 26...b5 or 26...b6. Or black could bring his queen more into the action with 26...Qb8. Are we really saying that for a Wednesday solution we need to analyse at least five different black replies (including the game line of 26...gxf5)?? For example, if black tries 26...Bf8, white's only move to keep the advantage is 27. Qg5 
click for larger viewNow what? Black has several possible choices. True, none of them work, but they all ought to be evaluated. That feels like a lot of messy work for a Wednesday. 26...Rxf5 is the best move, but I almost talked myself out of it because it felt too complicated for a midweek "medium/easy". |
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| Jun-01-16 | | dfcx: black has two extra pawns but white has the black king cornered. To tear down the black defense the knight must go! The intuitive 26. Bxf6 Bxf6 27.Qxh7+ Kf8 only nets a pawn for white. Instead, 26.Rxf5! The black knight is attacked by two white pieces and can't leave its duty to guard h7 pawn. Taking the rook is fatal, A. 26...gxf5? 27.Rg4+ Nxg4/Kh8 28, Qg7#
B. 26...Bf8 27.Qg5 Nd5/Nd7? 28.Rxh7 Kxh7 29.Qh4+ Bh6 30.Rxf7+ mates. C. 26...Qb8 27.Rxf6 Bxf6 28.Bxf6 Rxf6 29.Qxh7+ Kf8 30.Qh6+ Ke7 31.Qg5 wins the rook back. |
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| Jun-01-16 | | yadasampati: <dfcx> Your A-line is not quite right in my opinion. After 27. Rg4+ black has fxg4 and white looks lost. Or am i wrong? |
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| Jun-01-16 | | The Kings Domain: Tough puzzle. Missed it and I still don't get it. |
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| Jun-01-16 | | kevin86: I missed this one. Didn't even see the rook sac at f5! |
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| Jun-01-16 | | YouRang: Darn it -- I glanced at 26.Rxf5, but didn't follow the continuation deeply enough. I settled on a similar idea with <26.g4>, since <26...fxg4> opens the f-file <27.Bxf6> removes defender of Ph7 <...Bxf6 28.Qxh7 Kf8> 
click for larger view
Now <29.Nd5!>, and the benefit of opening the f-file pays off. We threaten Qxf7#, since f7 is hit by the N or (if ...Bxe5) the R. If 29...Rxe5 then 30.Rxf6  . If 29...Ke7, then 30.Qxf7+ Kd8 31.Rxf6 The problem is that 26...fxg4 isn't forced. Black has 26...Bf8 or 26...f4. White still has a good attack potential, but no slam dunk. ~~~~
Looking at 26.Rxf5! with the engine, I see that it has some subtleties that make me feel not-so-bad about missing it (e.g. 26...gxf5 isn't forced either). A tough Wednesday puzzle this week. |
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| Jun-01-16 | | Donjahz: Took me a while to see how White would win. It's simple - no matter where Black King moves, Rg4 is killer since Black Knight must take, but to no avail since Bishop covers Qg7#. |
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| Jun-01-16 | | patzer2: Tough week so far. Found Monday's solution quick, fell for the flawed game continuation Tuesday and for today's Wednesday puzzle the best I could find was 26. Rff4 = which fizzles out to a draw by repetiton after 26. Rff4 Bf8 27. Qg5 Bg7 28. g4 h6 (28... fxg4 ? 29. Rxf6  ) 29. Rxh6 Nxg4 30. Bxg7 Kxg7 31. Bxg4 e2 32. Bxe2 Rxe2 33. Qh4 Qb8 34. Rh7+ Kg8 35. Rh8+ Kg7 36. Rh7+ Kf8 37. Rh8+ Kg7 38. Rh7+ = (0.00 @ 21 depth, Deep Fritz 15). The Wednesday solution is of course the game move 26. Rxf5! The strongest reply, according to the computers is 26...Qb8 when White wins after 27. Rxf6 (+2.63 @ 34 depth, Stockfish 5 SE). Following the game continuation 26...gxf5, White forces mate-in-eight or less after <27. Qg5+! Kh8> (27... Kf8 28. Rxh7 Bd6 29. Bxf6 Rxf6 30. Qxf6 Bxh2+ 31. Rxh2 Bb5 32.
Rh8#) 28. Qxf5 Kg8 29. Qg5+ 1-0 (diagram below)
click for larger viewwhen in this final game position Black resigned in lieu of 29...Kf8 (29... Kh8 30. Rg4 Rg8 31. Qxg8#) 30. Qh6+ Kg8 31. Rg4+ Nxg4 32. Qg7#. Black's decisive mistake was 25...Be7? allowing 26. Rxf5! (+2.88 @ 30 depth, Stockfish 10). Instead, 25...b6 = (0.12 @ 23 depth, Komodo 8) holds it level. In the early middle game, White gained a strong advantage with the pawn sacrifice offer 19. f5! If 19...exf5? then 20. Nxe3! (+4.87 2 17 depth, Deep Fritz 15) is crusing. After 19. f5! Rae8, White could have gained a strong edge with 20. fxe6 fxe6 21. Rae1 when play might continue 21...Bd5 22. Nb6 Kh8 23. Qxe3 Bc6 24. Bf3 c4 25. dxc4 Bxf3 26. Rxf3 Ng4 27. Rxf8+ Rxf8 28. Qe4 Nxe5 29. Qxe5 (+2.12 @ 24 depth, deep Fritz 15). Even earlier, instead of 14...dxe3? allowing 15. Nxc6 (+1.32 @ 26 depth, Komodo 9.1), Black could have held the position with
14... Nd5 15. Nxc6 Bxc6 16. exd4 Bf6 = (-0.15 @ 24 depth, Stockfish 070614 SE). |
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Jun-01-16
 | | Willber G: Too difficult for a Wednesday (and yesterday was a mess). Come on CG, let's get back to normal. |
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| Jun-01-16 | | Patriot: <Once>/<gofer> I don't get it. After 26...Bf8 27.Qg5, isn't white just winning a pawn for nothing? I'm not saying it's winning but is it really something to worry about as white? Even after 27...h6 white could try 28.Qg3 I guess and hold on to the pawn. However I do agree 26...Bf8 is a worthwhile line to consider but it seems to fizzle out shortly. |
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| Jun-01-16 | | King.Arthur.Brazil: I saw that 26.Bxf6 Bxf6 27.Qxh7+ Kf8 leads to nothing since there's no move Rg4 for example. Then I saw 26.Rxf5 gxf5, but I still wondered abou Bxf6. Then comng to see the game, I see Qg5+ and Qxf5, but as I'm a little sleepy tonight, I dind't see the following. Give me a half point, for today is enought! lgs. |
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| Jun-02-16 | | stst: Too late for kibitz, but just consider two main lines:
A: 26.Rxf5
B: 26.Bxf6
both try to annihilate the defense by the N@f6 so that Qxh7+ can move ahead... |
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| Jun-02-16 | | SimplicityRichard: This is a brilliant puzzle; rather difficult.# |
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| Jun-02-16 | | YouRang: As others have pointed out, after 26.Rxf5!, black played the "natural" 26...gxf5, but it technically wasn't the stiffest defense for black. Suppose black played <26...Qb8> instead. Then, the continuation becomes a series of puzzles:
click for larger view
Now what?
Well, not too hard - white would like to remove the defender of Ph7, so <27.Bxf6 Bxf6 28.Qxh7+ Kf8>
click for larger view
Now what?
(a) Black's Bf6 is defended and white's Rf5 is attacked. Perhaps 29.Rf1 to get it back to safety? It still attacks the f-file, but can switch to e-to attack the pawn. (b) Howabout 29.Ne5, threatening Qxf7#? It's guarded by Rf5, and black can't take it with the B (29...Bxe5? 30.Qxf7#) or with the R (29...Rxe5 30.Rxf5 threatening Qxf7# and Qxg6/Rh7 ) (c) Maybe the exchange sac with 29.Rxf6 Rxf6 leads to better attack? It turns out that (c) is the correct answer. (a) leaves black better after 29...Ke7. (b) loses steam after 29...Qxe5! 30.Rxe5 Bxe5. <29.Rxf6! Rxf6>
click for larger view
Now what?
(a) Give check with 30.Qh8+ perhaps?
(b) Give check with 30.Qh6+ maybe?
(c) Howabout 30.g3 to control the important f4 square, eyed by the black Q and R? The correct answer is (b), and the other choices leave black better. <30.Qh6+ Ke7>
click for larger view
Now what?
(a) 31.Qg5 pinning the rook?
(b) 31.Qxe3+, capture the annoying pawn with check?
(c) 31.c3, supporting b or c pawn push?
Correct answer is (a). (b) and (c) both leave black better. <31.Qg5 Qc7>
click for larger view
Now what?
(a) 32.g3 to control f4?
(b) 34.c3, supporting d4 and b4?
(c) 34.d4, to transfer Rh4 to d-file after exchanging pawns. Answer: Each move is okay, but (a) stands out as best. <32.g3 Rd8 33.Qxe3+ Re6>
click for larger view
Now what?
(a) 34.Qxc5+, winning the pawn and pinning the LSB?
(b) 34.Qg5+, go back to g5 to give check?
(c) 34.Qf2, prepare for attack on Pf7?
The best answer by far is (b).
White is more clearly winning now, but it's still not trivial to find the best moves to finish it off. |
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Later Kibitzing> |
Kibitzing
sac: 26.Rxf5