Jul-21-23 | | jrredfield: I quickly saw 33 ... Nxc1+ 34 Rxc1 Rc3 35 b4 Rb3 threatening Rb1, but didn't see a quick path to leverage the pawn threat quite yet. Clearly a superior position for Black at this point, but not able to see it through so far. |
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Jul-21-23 | | Brenin: It has to be 33 ... Ra8, removing the White R from antipromotion duties. After 34 Rxa8 Nxc1+ 35 Ke3 (not 35 Kd2 Nxb3+ and 36 ... b1=Q) Black must play 35 ... Ne3, and not Nxb3 36 Ba3. Now 36 Ba3 is answered with 36 ... b4, and the White B is lost. The win is now clear. |
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Jul-21-23 | | jrredfield: I hadn't looked at the text move when I first posted. I don't see 33 ... Ra8 as all that effective. After 34 Rxa8 Nxc1+, nothing reveals itself as a winning advantage for Black. I think White could have eked out a draw from this position. Clearly White blundered a bit after this, but I haven't yet seen where. |
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Jul-21-23 | | mel gibson: I chose 33. .. Nxc1+ and Stockfish agrees with me: Stockfish 16 says:
33. .. Nxc1+
(33. .. Nxc1+ (Nd3xc1+ Ra1xc1 Rc8-c3 b3-b4 h5-h4 Bd6-c5 Rc3-b3
g2-g4 Kh7-g8 Bc5-e7 h4-h3 Be7-c5 Kg8-f7 Ke2-d2 Rb3-b1 f3-f4 Bg6-e4 Bc5-e3
Rb1-b3 Be3-c5 Kf7-e8 Rc1-e1 Rb3-b1 Bc5-f2 ) +4.92/43 159) score for Black +4.92 depth 43
If I force SF to play the game ply -
it is close to a draw:
33. Ke2 Ra8
34. Rxa8
(34. Rxa8 (Ra1xa8 Nd3xc1+ Ke2-e3 Nc1xb3 Bd6-a3 b5-b4
Ba3-b2 c2-c1R Bb2xc1 Nb3xc1 Ra8-b8 b4-b3 Ke3-d2 Nc1-d3 Rb8xb3 Nd3xe5 Kd2-e3
Kh7-h6 Rb3-b5 Ne5-c4+ Ke3-d4 Nc4-d6 Rb5-b4 Nd6-f7 h2-h4 Bg6-f5 Kd4-e3
Nf7-e5 Rb4-b5 Ne5-g6 g2-g3 Ng6-e7 Ke3-d4 Kh6-h7 Kd4-e5 Kh7-g6 Rb5-b6 Ne7-d5
) -0.35/60 162)
score for White -0.35 depth 60. |
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Jul-21-23
 | | perfidious: Came into this POTD not thinking on the right lines, for which retribution at the board is so often swift and sure. |
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Jul-21-23 | | Brenin: ... or maybe not so clear if White plays 37 Kd2, rather than Bb2, e.g. 37 ... bxa3 38 Kxc2 Nf4+ 39 Kd2 Nxg2 40 Rxa3 looks drawn, or 37 ... Nc5 38 Bb2 Nxb3+ 39 Ke3 c1=Q+ 40 Bxc1 Nxc1 41 Rb8 Na2 and Black still has work to do. So maybe <jrredfield> is right, and 33 Nxc1+ is the way forward. |
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Jul-21-23 | | Mayankk: I saw the workmanlike 33 ... Nc1+ 34 Rxc1 Rc3 35 b4 Rb3 36 Kd2 Rb1 37 Rxc2 (else White will stay tied to defending against the c2 pawn and Black King will march ahead) Bxc2 38 Kxc2 Rh1. Now the Black Rook will gobble the f-g-h pawns as both White King and Bishop are away from action. Should be winning for Black. I didn't notice the fireworks on 33 ... Ra8 line although I did briefly ponder over it. Whether this line wins or draws, it definitely seems more a puzzle solution than the prosaic 33 ... Nc1+. |
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Jul-21-23 | | raymondhow: I really wanted to play 33...Nf4+ which the engine gives as best, but instead chose 33...Rc3 which gains only small advantage. |
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Jul-21-23 | | King.Arthur.Brazil: It is unbelivable: 33...Ra8! 34. Rxa8 Nxc1+ 35. Kd2? Nxb3+ 36. Ke2 c1=Q. Also 35. Ke1 (or Kf2) Nd3+ and 36... c1=Q. Therefore, the probably answer must be 35. Ke3 (where there's no N checks) ... Nxb3, 36. Ba3 c4!? 37. Bb2 c1=Q, 38. Bxc1 Nxc1 39. Rc8 Na2 (or Nd2) and this ♙ will go promote too. If White try to sacrifice the ♗, 34. Ba3?! Rxa3 35. Rxa3 Nxc8+ 36... Nxb3 and c1=Q next. It don't solve either: 34. Nxd3 Rxa1 35. Kd2 Bxd3 also c1=Q next. Other possibility is 4. Rxa8 Nxc1+ 35. Ke3 Nxb3 36. Rc8 c1=Q+ 37. Rxc1 Nxc1 38. Kd2 Nd3, with an extra ♘. |
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Jul-21-23 | | agb2002: The white rook protects the knight and the promotion square c1. Hence, 33... Ra8: A) 34.Rxa8 Nxc1+ 35.Ke3 (35.Kd2 Nxb3+ and 36... c1=Q wins) 35... Nd3 (35... Nxb3 36.Ba3 b4 37.Bb2 c1=Q+ 38.Bxc1 Nxc1 looks more complex) 36.Ba3 (36.Rc8 c1=Q+ 37.Rxc1 Nxc1 - + [n vs P]) 36... b4 A.1) 37.Bc1 Nxc1 followed by Nxb3 wins decisive material. A.2) 37.Bb2 Nxb2
A.2.a) 38.Kd2 Nd1 39.Rb8 Nc3 40.Rxb4 (40.Ra8 Ne2) 40... Na2 41.Rc4 c1=Q+ 42.Rxc1 Nxc1 43.Kxc1 Kg8 - + [b vs 2P]. A.2.b) 38.Rc8 Nd1+ 39.Kd2 Nc3 looks similar to A.2.a. B) 34.Na2 Rxa2 wins decisive material.
C) 34.Nxd3 Rxa1 35.Kd2 Bxd3 wins decisive material. |
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Jul-21-23 | | King.Arthur.Brazil: In the game line, 42. g3 Nb1+ 43. Kc1 Bd3 44. Kb2 Nc3 45. Rc1 Ne2 46. Rxc2 Bxc2 47. Kxc2 Nxg3 48. Kd3 Kg6 49. Kc4 Nf5 50. Kxb4 Nxh4 51. f4 Nf5 52. Kc5 h4 53. b4 h3 54. b5 h2 55. b6 h1=Q the end. Other way is 40...h4 41. g3 h3 42. g4 Kh6 43. f4 Nb1+ 44. Kc1 Nc3 45. Kb2 Ne2 46. Rc1 Bd3 47. Rxc2 Bxc2 48. Kxc2 Nxf4 49. Kd2 Kg5 (Block the White ♔) 50. Ke3 Kxg4 51. Kd4 Nd5 52. Kc5 Kf5 53. Kd6 g5 and ♙ e5 is captured too. I like this line because the White ♔ has little chances of counter attack. |
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Jul-21-23 | | agb2002: I missed 37.Kd2 in my line A, opposing some resistance and 40... c1=Q+ in my line A.2.a. |
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Jul-21-23 | | Refused: the c2 pawn is the pride and joy of black's position. Alas, for the moment it's block. Normal means like Nxc1 Ra2-b2-b1 are too slow to get us anywhere. Thus. 33...Ra8!! 34.Rxa8 (what else) Nxc1+ and this is winning now. Black will win the Bishop after something like 35.Ke3d Nd3 36.Ba3 b4! 37.Bb2 Nxb2 should be winning as the c2 is still alive and black has basically traded his rook for white's two minor pieces. |
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Jul-21-23 | | Socrates2: Again, not everyhing was clearly forced. |
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Jul-21-23 | | Socrates2: Also, I don't see a clear denoument. |
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Jul-21-23
 | | scormus: I confess to not considering 33 ...Ra8, and when I saw the text I thought my choice of ... Nxc1 must have missed the best route. However, it did look to me it would be winning in a rather plodding way following what I see is also the <jrredfield> and <mel/SF> line. W's 35 b4 shuts the bishop out of any defence of the Kside, and that will be decisive. |
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Jul-21-23
 | | Teyss: <Mayankk: I saw the workmanlike 33... Nc1+ 34 Rxc1 Rc3 35 b4 Rb3 36 Kd2 Rb1 37 Rxc2 (else White will stay tied to defending against the c2 pawn and Black King will march ahead)> White should not take the c2 P: he is tied but so is Black as long as he leaves the R on b1. If it moves, the WR or WK can also move albeit with less space than Black who still has some work to do (-2.0 at 34 ply). Action will happen on the Kside to gain space and push the Ps forward. Summary:
- 33...Ra8 doesn't win although psychologically it's a good move giving White issues to solve: indeed he went astray with 37.Bb2? instead of Kd2 as noted. But then nobody likes to put his K in potential discovery check after 38.Kxc2.
- 33...Nxc1+ gives Black an edge, who still needs to convert his advantage (-2.8 at 36 ply).
- 33...Nf4+ pointed by <raymondhow> also gives an edge: 34.Kd2 Nxg2 and White is short of a P with a destroyed structure (-2.6 at 38 ply). If 34.Kf1 or Kf2 to defend the g2 P, there are many variations but in short White's position is crammed and passive. |
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Jul-21-23
 | | chrisowen: I bon its same forth its work quip its hud luggy its jove Ra8 faith Nxc1+ arrived its odd its hoh adagio its nag bib vim Ra8 bug Nxc1+ eh? |
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Jul-21-23 | | thegoodanarchist: Brilliant combo by Bisquier |
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Jul-21-23 | | Mayankk: Hi <Teyss>, Thanks for your reply. If the c2 pawn is not taken, then what stops Black from advancing his King all the way from h7 to b2 via g8-f7-e8-d7-c6-d5-d4-b3 ? Seems like a choice between slow death and a quick one. |
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Jul-21-23
 | | Teyss: Hi <Mayankk> You're right. Black can place his R on b3 to prevent the WK from blocking the way. |
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