Answers.Body: <p><strong>TL;DR</strong> This is likely a winning position for White.</p>
  <p><strong>Details:</strong><br />
  In Spassky–Geller (Tbilisi, 1959), Geller resigned after <strong>75. Nc1</strong> (<a href="https://www.chessgames.com/perl/chessgame?gid=1048900" rel="nofollow noreferrer">game</a>).</p>
  <p>While we don't know what <em>perfect play</em> is, we can approximate <em>very good play</em> which shows Black is likely lost. After <strong>75. Nc1</strong>, Stockfish 14+ NNUE gives this position +1.8 (depth = 50, 11379k nodes/s).</p>
  <p><strong>Methodology:</strong> For each move, I used Stockfish 14+ NNUE to calculate to a minimum depth of 40 ply (half-moves, or 20 moves for both players) for a single, principal variation. I make that single ply for one player, then begin the calculation again. The diagram below shows the resulting <em>very good play</em>.</p>
  <p>Black harasses the White King with checks, pins pieces, and eventually advances a pawn to the third rank. White begins with the King rushing over from the a-file to the pawns before slowly making progress through excellent piece coordination eventually reaching a <a href="https://syzygy-tables.info/?fen=6q1/3k4/8/5PB1/4N1K1/5B2/8/8_w_-_-_0_1" rel="nofollow noreferrer">tablebase win for White</a> after <strong>59...Qxg8</strong>.</p>
  <pre><code>[Title &quot;Analysis starting after 75. Nc1&quot;]
  [FEN &quot;6k1/6p1/7p/7P/2q1B1P1/Kp1N1P2/1B6/8 w - - 14 75&quot;]
  
  1. Nc1 {+1.8, depth = 50, 11379k nodes/s} Qa6+ 2. Kxb3 Qb6+ 3. Kc2 Qf2+ 4. Kc3 Qc5+ 5. Kd2 Qf2+ 6. Ne2 Kh8 7. Bd4 Qh4 {+2.8, depth = 45, 12131k nodes/s} 8. Be3 Qd8+ 9. Ke1 Qa5+ 10. Kf2 Qa2 11. Bd3 Qb2 12. Kg2 Kg8 {+3.6, depth = 48, 13785k nodes/s} 13. Kh3 Qa3 14. Nf4 Qc3 15. Bf2 {+3.9, depth = 43, 12227k nodes/s} 15...Qd2 16. Kg3 Kf7 17. Ng6 {+4.4, depth = 41, 13075k nodes/s} 17...Qc1 {+4.6, depth =40, 13058k nodes/s} 18. Nh4 Qc3 19. Bg6+ Ke6 20. Be4 Qe5+ 21. Kg2 Qb2 22. Nf5 Kd7 {+5.2, depth = 42, 3694k nodes/s} 23. f4 Ke6 24. Bf3 Kf7 {+9.1, depth = 39, 12275k nodes/s} 25. Bd5+ {+9.4, depth = 42, 12717k nodes/s} Kf6 {+9.9, depth = 43, 12347k nodes/s} 26. Kg3 Qc3+ 27. Bf3 Kf7 28. Bd4  Qe1+ {+8.9, depth = 40, 13842k nodes/s} 29. Kh2 Qd2+ 30. Kh3 Qd3 31. Kg3 g6 32. Nxh6+ Kf8 {+53.3, depth = 45, 11736k nodes/s} 33. Be5 gxh5 34. g5 Ke7 35. Ng8+ Ke6 36. Nf6 {+54.1, depth = 50, 5641k nodes/s} h4+ 37. Kg4 h3 38. Ne4 Qe3 39. Bd6 Qg1+ 40. Kxh3 Qf1+ 41. Bg2 Qd3+ 42. Kh4 Qe2 43. f5+ Kd7 44. Kh3 Kd8 45. Bf4 Ke7 46. Kg3 {+99, depth = 41, 5800k nodes/s} Qe1+ 47. Kg4 {Mate in 24, depth = 53, 7314k nodes/s} 47...Qg1 48. Kh3 Qa1 49. g6 Qd1 50. Ng3 Qd4 51. Kg4 Ke8 52. Bf3 Ke7 53. Ne4 Qg1+ 54. Bg3 Qc1 55. Bd6+ Kd7 56. g7 Qc8 57. Bf4 Ke7 58. Bg5+ Kd7 59. g8=Q Qxg8 {Tablebase Win for White} 60. Nf6+ Kd8 61. Nxg8+ Kc7 62. f6 Kb6 63. f7 Ka5 64. f8=Q Ka4 65. Qb8 Ka3 66. Bd2 Ka2 67. Bd5+ Ka1 68. Bc3#
  </code></pre>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2021-12-09T06:04:14.667Z
Answers.Text: 37 Ke7 must be a typo or some missing moves.
Answers.UserDisplayName: Gerry
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2021-12-09T13:17:32.277Z
Answers.Text: @Gerry my mistake!  I'll correct when I get back to my notes.
Answers.UserDisplayName: SecretAgentMan
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2021-12-09T14:26:47.923Z
Answers.Text: @Gerry I corrected the typo and revalidated the continuation after **36...h4+** .
Answers.UserDisplayName: SecretAgentMan
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2021-12-09T04:28:09.000Z
Answers.LastActivityDate: 2021-12-09T14:26:05.977Z
Answers.LastEditDate: 2021-12-09T14:26:05.977Z
Answers.UserDisplayName: SecretAgentMan
Body: <p>Did Geller resign in a drawn position vs Spassky in 1959? Or could White win? Here is the famous controversial position, Black to move.</p>
  <pre><code>[FEN &quot;6k1/6p1/7p/7P/2q1B1P1/Kp3P2/1B6/2N5 b - - 0 1&quot;]
  [startflipped &quot;&quot;]
  </code></pre>
  
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2021-11-24T21:52:32.007Z
Comments.Text: Regarding 50/75, note that this rule was modified numerous times, and maybe you first must find out which version was in effect. Concerning win, even without 50 this is tricky, as White must gang up the pawns, but needs the knight, so it can't be used for shielding the king.
Comments.UserDisplayName: Hauke Reddmann
Tags: <analysis><draw><famous-games><spassky>
Title: Did Geller resign in a drawn position vs Spassky in a 1959 game?
ThreadText: # Did Geller resign in a drawn position vs Spassky in a 1959 game?
  
  (Asked by: username_0 on 2021-11-24)
  
  Did Geller resign in a drawn position vs Spassky in 1959? Or could White win? Here is the famous controversial position, Black to move.
  [FEN "6k1/6p1/7p/7P/2q1B1P1/Kp3P2/1B6/2N5 b - - 0 1"]
  [startflipped ""]
  
  **Tags:** analysis, draw, famous-games, spassky
  
  > **Comments:**
  > **username_1**: Regarding 50/75, note that this rule was modified numerous times, and maybe you first must find out which version was in effect. Concerning win, even without 50 this is tricky, as White must gang up the pawns, but needs the knight, so it can't be used for shielding the king.  
  
  ---
  
  ## 1 answers
  
  ### Answer by username_2 on 2021-12-09. Score: 1
  
  TL;DR This is likely a winning position for White.
  Details:
  In Spassky–Geller (Tbilisi, 1959), Geller resigned after 75. Nc1 (game).
  While we don't know what perfect play is, we can approximate very good play which shows Black is likely lost. After 75. Nc1, Stockfish 14+ NNUE gives this position +1.8 (depth = 50, 11379k nodes/s).
  Methodology: For each move, I used Stockfish 14+ NNUE to calculate to a minimum depth of 40 ply (half-moves, or 20 moves for both players) for a single, principal variation. I make that single ply for one player, then begin the calculation again. The diagram below shows the resulting very good play.
  Black harasses the White King with checks, pins pieces, and eventually advances a pawn to the third rank. White begins with the King rushing over from the a-file to the pawns before slowly making progress through excellent piece coordination eventually reaching a tablebase win for White after 59...Qxg8.
  [Title "Analysis starting after 75. Nc1"]
  [FEN "6k1/6p1/7p/7P/2q1B1P1/Kp1N1P2/1B6/8 w - - 14 75"]
  
  1. Nc1 {+1.8, depth = 50, 11379k nodes/s} Qa6+ 2. Kxb3 Qb6+ 3. Kc2 Qf2+ 4. Kc3 Qc5+ 5. Kd2 Qf2+ 6. Ne2 Kh8 7. Bd4 Qh4 {+2.8, depth = 45, 12131k nodes/s} 8. Be3 Qd8+ 9. Ke1 Qa5+ 10. Kf2 Qa2 11. Bd3 Qb2 12. Kg2 Kg8 {+3.6, depth = 48, 13785k nodes/s} 13. Kh3 Qa3 14. Nf4 Qc3 15. Bf2 {+3.9, depth = 43, 12227k nodes/s} 15...Qd2 16. Kg3 Kf7 17. Ng6 {+4.4, depth = 41, 13075k nodes/s} 17...Qc1 {+4.6, depth =40, 13058k nodes/s} 18. Nh4 Qc3 19. Bg6+ Ke6 20. Be4 Qe5+ 21. Kg2 Qb2 22. Nf5 Kd7 {+5.2, depth = 42, 3694k nodes/s} 23. f4 Ke6 24. Bf3 Kf7 {+9.1, depth = 39, 12275k nodes/s} 25. Bd5+ {+9.4, depth = 42, 12717k nodes/s} Kf6 {+9.9, depth = 43, 12347k nodes/s} 26. Kg3 Qc3+ 27. Bf3 Kf7 28. Bd4  Qe1+ {+8.9, depth = 40, 13842k nodes/s} 29. Kh2 Qd2+ 30. Kh3 Qd3 31. Kg3 g6 32. Nxh6+ Kf8 {+53.3, depth = 45, 11736k nodes/s} 33. Be5 gxh5 34. g5 Ke7 35. Ng8+ Ke6 36. Nf6 {+54.1, depth = 50, 5641k nodes/s} h4+ 37. Kg4 h3 38. Ne4 Qe3 39. Bd6 Qg1+ 40. Kxh3 Qf1+ 41. Bg2 Qd3+ 42. Kh4 Qe2 43. f5+ Kd7 44. Kh3 Kd8 45. Bf4 Ke7 46. Kg3 {+99, depth = 41, 5800k nodes/s} Qe1+ 47. Kg4 {Mate in 24, depth = 53, 7314k nodes/s} 47...Qg1 48. Kh3 Qa1 49. g6 Qd1 50. Ng3 Qd4 51. Kg4 Ke8 52. Bf3 Ke7 53. Ne4 Qg1+ 54. Bg3 Qc1 55. Bd6+ Kd7 56. g7 Qc8 57. Bf4 Ke7 58. Bg5+ Kd7 59. g8=Q Qxg8 {Tablebase Win for White} 60. Nf6+ Kd8 61. Nxg8+ Kc7 62. f6 Kb6 63. f7 Ka5 64. f8=Q Ka4 65. Qb8 Ka3 66. Bd2 Ka2 67. Bd5+ Ka1 68. Bc3#
  
  > **Comments:**
  > **username_3**: 37 Ke7 must be a typo or some missing moves.  
  > **username_2**: @username_3 my mistake!  I'll correct when I get back to my notes.  
  > **username_2**: @username_3 I corrected the typo and revalidated the continuation after **36...h4+** .  
  
  ---
  
  