Jul-24-25 | | Walter Glattke: a) 44.-Bxf3+ 45. Kxf3 Rf6+ 46.Ke2 Qh5+ 47.Ke1 Rxf1+ 48.Kxf1 h2 49.Nf2 h1Q+ 50.Nxh1 Qxh1+ 51.Ke2 Qxc1 52.Rb8+ (>Qc2 rook lose) Kh7 -++ b) 44.-Qh5 45.f4 h2 46.Rh1 Qh3 47.Kf3 Rg6 48.Qc2 Rxg3+ 49.Ke2 Qg2+ 50.Nf2 R6xe3+ 51.Rxe3 Rxe3+ 52.Kd1 Qg1+ 53.Rxg1 hxg1Q# |
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Jul-24-25 | | King.Arthur.Brazil: The king's line is not so immediate: 44...Rxf3+ 45. Kxf3 Rf6+ 46. Ke2 Qh5+ 47. Ke1 Rxf1+ 48. Kxf1 Qf3+ (49. Kg1? Qg2#) 49. Nf2 h2 50. Rb8+ Kf7 51. Rb7+ Ke6 52. Ke1 h1=Q+ 53. Nxh1 Qxh1+ 54. Ke2 Qxc1, win our beloved ♕ from our enemy. Or 49. Ke1 h2 50. Rb8+ Kf7 51. Rb7+ Ke6 52 Nf2 h1=Q+ 53. Nxh1 Qxh1+ 54. Ke2 Qxc1 and win too. Obviously B cannot play 50... Kh7?? due to 51. Qb1+ Kh6 52. Rh8+ and Rxh2, when B is lost. |
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Jul-24-25
 | | takebackok: Keep checking might be Thursday, forcing easy line 44...Rxf3 45. Kxf3 Rf6+ 46. Ke2 Qh4+ 47. Ke1 Rxf1+ 48. Kxf1 h2 49. Nf2 h1=Q 50. Nxh1 Qxh1+ 51. Kf2 Qxc1 gg. |
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Jul-24-25 | | olinart: Rxf3+ stands out because the K's escape squares are so restricted. My line is very similar to the game line
44...Rxf3+ 45. Kxf3 Qh5+ 46. Kf2 Rf6+ 47. Kg1 Rxf1+
48. Kxf1 h2 h1=Q+ 50. Nxh1 Qxh1+ |
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Jul-24-25 | | mel gibson: I saw that.
Stockfish 17 says:
44. .. Rxf3+
(44. .. Rxf3+ (1. ... Rxf3+ 2.Kxf3 Rf6+ 3.Ke2 Qh5+ 4.g4 Qxg4+ 5.Ke1 Qg3+
6.Ke2 h2 7.Nf2 Rxf2+ 8.Rxf2 Qg4+ 9.Rf3 Qg2+ 10.Rf2 h1Q 11.Qxh1 Qxh1 12.Rb8+
Kh7 13.Rb3 Qc1 14.Rb8 Qxe3+ ) +9.82/44 745)
score for Black +9.82 depth 44. |
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Jul-24-25 | | bcokugras: Congratulations Yagiz! Wish you all the luck & success with your chess career. |
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Jul-24-25 | | vajeer: While the initial idea is easy to spot, this is more difficult to play on board than it seems as one needs to look 10 odd plies ahead and check couple of defenses to make sure the sacrifice is going to work.
47. g4 is a nice defence and one potential line that needs to be analyzed before making the sacrifice:
47. g4 Qxg4+ 48. Ke1 Qg3+ 49. Nf2
 click for larger viewh2 50. Qc2 Nxe3 51. Rxe3 Qxe3+ 52. Qe2 Qc1+ 53. Nd1 Qh6 54. Rh1 Re6 -+
 click for larger view |
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Jul-24-25 | | TheaN: <44....Rxf3+> is kind of the move that jumps out immediately, given Black wants access to the White king and otherwise f4 follows quite soon. It's quite a journey to calculate Black wins the rook back or h goes. <45.Kxf3> else Rxe3 or Rxg3 -+ <45....Rf6+ 46.Ke2 (Kg5 Qe6+ -+) Qh5+ 47.g4> by far the best try, 47.Kd3? Rxf1 -+, 47.Ke1, the text is the logical move but loses swiftly after 47....Rxf1+ 48.Kxf1 h2, checks dry up after 49.Rb8+ Kf7 50.Rb7+ Ke6 -+ <47....Qxg4+ 48.Ke1 Qxg3+ 49.Nf2 Rxf2! 50.Rxf2 h2 51.Ke2> 51.Rb8+ is a try because if not 51....Qxb8 White gets too active, but this is still fairly easily winning an exchange down, due to h2 and two pawns <51....Qg4+ 52.Rf3> 52.Kd3 perhaps best but 52....Qe4+ with 53....h1Q -+ is simple <52....Qg2+ 53.Rf2 h1Q -+>:
 click for larger view
Eight moves later and Black forces ♕♘:♖♖. Fairly complicated for a Thursday, but once you see the h-pawn goes it kind of plays itself. |
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Jul-24-25
 | | chrisowen: I nom c v its fuel its pay its Rxf3+ its aed its odd fa its abb its lab v its abridge its lip Rxf3+ fig x |
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Jul-24-25 | | Cellist: <Olinart>: Your solution, which I also favored, does not work because White can play g4 after the Q check, and g4 is now defended by the White K. So after 44...Rxf3+ 45. Kxf3 Qh5+ 46. g4, Black looses quickly. The combination you outline only works if White withdraws with 46. Kf2, which brings us to the game line, but 46. g4 turns the tables. This shows again how important move order is! |
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Jul-24-25
 | | chrisowen: Flick f3 count xxx |
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Jul-24-25 | | alshatranji: A question about Stockfish. If I use the engine to find the best 44 move for Black, it gives me 44...Qg6 at -5.01. But if I enter 44...Rxf3+, it gives me -5.58. So can't Stockfish tell the best move immediately? Is this the difference that one ply makes? And then how reliable is Stockfish for analysis? Or is this only the free version? |
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Jul-24-25 | | vajeer: <alshatranji:> version could be one reason. Latest version may choose a different move. Perhaps someone with more hands on experience can explain better. Here are my two cents - apart from version, this can also happen because computer programs still haven't solved chess. And so once in a while they fail to identify the best moves. We have seen that in the past. But once you manually feed the best move, it shows it to be the best.
So, I would say SF is reliable just leave maybe 5% chance that it failed to identify the best move. |
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Jul-24-25 | | King.Arthur.Brazil: <Alshatranji><Vajeer> A very interesting question. Let the king give two cents too. When we look into the final position, B has ♕+♘ x♖ is a clearly winning position. However, my suspicion is that -maybe- the algorithm do a balance where W lose ♕+♖+♘+♙ and B lose ♕+2♖, because the ♙ crowned, so in reality the evaluation would be W lose ♕+♖+♘+♙ and B 2♖+♙ which clearly is advantage. |
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Jul-24-25 | | TheaN: <alshatranji: A question about Stockfish. (...) Is this the difference that one ply makes?> Essentially you answered it yourself, yes, that's it. Depending on computing strength the engine simply isn't far enough (in pure brute force calculation, if NNUE is taken into the equation it becomes more complicated) to 'see' Rxf3+ is superior to Qg6. If you force the first move, you omit all other lines branching from black 44 which makes a huge difference. We analyze very concrete, computers brute force. AI... lets keep it at a mix. |
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Jul-24-25
 | | scormus: Might 49 Rb8+ have been worth a try, hoping for ... Kh7?? If instead ... Kf7, then 0-1 |
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Jul-24-25 | | alshatranji: Thank you TheaN and vajeer. This makes sense. I used to take it for granted that Stockfish would give the best move any any given time, but now I know better. I guess it goes to show how complex our game is, and perhaps (considering that an advanced chess program could not find the best move in a "medium" position) that the human mind is still superior in some ways. |
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Jul-25-25 | | Halldor: I quickly found 44... RxP† 45 KxR. Then I wanted to play Q-R4†, but fortunately I saw that White could then interpose the Knight Pawn, so I first had to check with the second Rook — as already mentioned here. The move order matters! |
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