Three positional sacrifices by Leela, very nice strategic game

[Nay Lin Tun]

Capture 6.PNG

Capture 5.PNG

cap4.png

[pgn][Event "Lc0 T35 vs SFDev (2x2070 vs TR1-12c)"] [Site "?"] [Date "2019.01.01"] [Round "57.1"] [White "Stockfish 18122721"] [Black "LCZero v20-rc2-32329"] [Result "0-1"] [BlackElo "3247"] [ECO "E31"] [Opening "Nimzo-Indian"] [Variation "Leningrad, Main Line, 8...e5 9.Qc2"] [WhiteElo "3519"] [TimeControl "1200+2"] [Termination "normal"] [PlyCount "383"] [WhiteType "human"] [BlackType "human"] 1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. Bg5 h6 5. Bh4 c5 6. d5 Bxc3+ 7. bxc3 d6 8. e3 e5 9. Qc2 Qe7 10. Nf3 Nbd7 11. Nd2 Kd8 12. f3 g5 13. Bg3 Nb6 14. Bd3 h5 15. h3 Rg8 16. a4 a5 17. h4 g4 18. Qb1 Kc7 19. f4 e4 20. Bc2 Bf5 21. O-O Nc8 22. Qb5 Re8 23. Ra2 Ng8 24. Qb1 Nh6 25. Bf2 g3 26. Bxg3 Ng4 27. Re1 b6 28. Bd1 Nf6 29. Nf3 Qf8 30. Ne5 Qg8 31. Bh2 Qh7 32. Ra3 Rg8 33. Rf1 Rf8 34. Qb5 Na7 35. Qb2 Qg7 36. Rf2 Rfd8 37. Rb3 Nc8 38. Qb1 Ra6 39. Rbb2 Ra8 40. Rbd2 Rg8 41. Qb5 Na7 42. Qb3 Qh7 43. Rb2 Rgb8 44. Be2 Rb7 45. Rf1 Qg7 46. Rfb1 Rg8 47. Bd1 Rf8 48. Qc2 Qh7 49. Qf2 Rc8 50. Rb3 Rcb8 51. Qb2 Qg8 52. Qa2 Qh7 53. R1b2 Ra8 54. Qb1 Rab8 55. Kf1 Ng8 56. Be2 Ne7 57. Kf2 f6 58. Kg1 Ng6 59. Nxg6 Qxg6 60. Ra3 Rg8 61. g3 Nc8 62. Rab3 Bd7 63. Bf1 Re8 64. Kh1 Rb8 65. Be2 Qf5 66. Kg1 Rb7 67. Bf1 Qg4 68. Be2 Qf5 69. Bf1 Qg4 70. Be2 Qg6 71. Kf2 Rb8 72. Ke1 Rg8 73. Bf1 Re8 74. Bg2 Bf5 75. Rb5 Ra8 76. Rf2 Ra6 77. Ke2 Ne7 78. Rb3 Bd7 79. Bxe4 f5 80. Bf3 Bxa4 81. Ra3 Bd7 82. Kf1 Ng8 83. Qe1 Nf6 84. Rb2 Ne4 85. Kg2 Rg8 86. Kf1 Raa8 87. Kg2 Ra7 88. Rab3 Rb7 89. Ra3 Rbb8 90. Qa1 Ra8 91. Qe1 a4 92. Be2 Qf7 93. Bf3 Qf6 94. Kh3 Qg6 95. Kg2 Ra5 96. Rba2 Ra7 97. Be2 Raa8 98. Rb2 Qg7 99. Bf3 Qh8 100. Kh1 Qh7 101. Be2 Be8 102. Bd3 Qg6 103. Rg2 Bd7 104. Bg1 Nf6 105. Be2 Rgb8 106. Qc1 Re8 107. Bf3 Re4 108. Bxe4 Nxe4 109. Kh2 Qg4 110. Qc2 Nf6 111. Rf2 Kb7 112. Ra1 Ne4 113. Rg2 Qf3 114. Rb1 Nf6 115. Qb2 Ra6 116. Qc2 Ng4+ 117. Kh1 Nf6 118. Ra1 Kc7 119. Kh2 Ra8 120. Rb1 Re8 121. Qb2 Rb8 122. Qc2 Re8 123. Qb2 Ng4+ 124. Kh1 Rb8 125. Qc2 Ra8 126. Ra1 Kb7 127. Rb1 a3 128. Qb3 Ra6 129. Qc2 Kc7 130. Ra1 Bc8 131. Qb1 Ra5 132. Qc2 Ra8 133. Qb1 Nf6 134. Kh2 Ng4+ 135. Kh1 Nf6 136. Kh2 Ra5 137. Qc2 Ra6 138. Qb1 Ng4+ 139. Kh1 Nf6 140. Kh2 Ra8 {3-fold repetition} 141. Qb5 Bb7 142. Qb1 Bc8 {3-fold repetition} 143. Kh1 {3-fold repetition} Ra5 144. Qd3 Ne4 145. Kh2 Ba6 146. Raa2 Kb8 147. Bf2 Nf6 148. g4 Nxg4+ 149. Kh1 Qe4 150. Qxe4 fxe4 151. Rxg4 hxg4 152. h5 Bxc4 153. h6 Ra7 154. Rxa3 Rh7 155. Kg2 Rxh6 156. Ra1 Kb7 157. f5 Rf6 158. Bg3 Rxf5 159. Bxd6 Rxd5 160. Bf4 Be2 161. Kg3 Bf3 162. c4 Rd2 163. Rc1 Rb2 164. Be5 Ra2 165. Kf4 Kc6 166. Kf5 Ra4 167. Rc2 Bd1 168. Rd2 Bb3 169. Rd6+ Kb7 170. Kxg4 Bxc4 171. Rd7+ Ka6 172. Kf4 Bd3 173. Bf6 Ra3 174. Rc7 Rb3 175. Ke5 Bc2 176. Kf4 Rd3 177. Rc6 Kb5 178. Re6 Rd5 179. Be5 Rd7 180. Rh6 Rb7 181. Rh2 Bd3 182. Kf5 Kc4 183. Ke6 b5 184. Kd6 b4 185. Rb2 Rb6+ 186. Kd7 Ra6 187. Rg2 Kb5 188. Rh2 Rg6 189. Ke7 c4 190. Rh5 Ka4 191. Rh1 c3 192. Kf7 0-1 [/pgn]

25. ....g3!!! Sacrifice a pawn to open "g"file.
78.....Bd7 (sacrifice center pawn to open "e" file.
107....Re4!!! Sacrifice a rook! Leela see a knight a center is better than a rook, so sacrificed a rook and keep her knight.

From Stockfish POV, Stockfish also sacrificed a knight in the centre, in exchange for two centre pawn, but Leela did not take the knight

[jorose]

Really nice game!

Second pawn sacrifice wasnt a sacrifice though, as a4 drops. Proper term for the Re4 move is an exchange sacrifice (rook for bishop or knight). Rook sacrifice generally implies only pawns and favorable board transformation as compensation.

Probably SFs unusual Nd2-f3-e5 maneuver was my favorite move sequence in the game. I don't know if the knight can be taken in any way at any point, but there is something fascinating about how long (almost 30 full moves!) that knight was en-prise, with neither side seeming to care.

[MikeGL]

Capture 6.PNGCapture 5.PNGcap4.png[pgn][Event "Lc0 T35 vs SFDev (2x2070 vs TR1-12c)"] [Site "?"] [Date "2019.01.01"] [Round "57.1"] [White "Stockfish 18122721"] [Black "LCZero v20-rc2-32329"] [Result "0-1"] [BlackElo "3247"] [ECO "E31"] [Opening "Nimzo-Indian"] [Variation "Leningrad, Main Line, 8...e5 9.Qc2"] [WhiteElo "3519"] [TimeControl "1200+2"] [Termination "normal"] [PlyCount "383"] [WhiteType "human"] [BlackType "human"] 1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. Bg5 h6 5. Bh4 c5 6. d5 Bxc3+ 7. bxc3 d6 8. e3 e5 9. Qc2 Qe7 10. Nf3 Nbd7 11. Nd2 Kd8 12. f3 g5 13. Bg3 Nb6 14. Bd3 h5 15. h3 Rg8 16. a4 a5 17. h4 g4 18. Qb1 Kc7 19. f4 e4 20. Bc2 Bf5 21. O-O Nc8 22. Qb5 Re8 23. Ra2 Ng8 24. Qb1 Nh6 25. Bf2 g3 26. Bxg3 Ng4 27. Re1 b6 28. Bd1 Nf6 29. Nf3 Qf8 30. Ne5 Qg8 31. Bh2 Qh7 32. Ra3 Rg8 33. Rf1 Rf8 34. Qb5 Na7 35. Qb2 Qg7 36. Rf2 Rfd8 37. Rb3 Nc8 38. Qb1 Ra6 39. Rbb2 Ra8 40. Rbd2 Rg8 41. Qb5 Na7 42. Qb3 Qh7 43. Rb2 Rgb8 44. Be2 Rb7 45. Rf1 Qg7 46. Rfb1 Rg8 47. Bd1 Rf8 48. Qc2 Qh7 49. Qf2 Rc8 50. Rb3 Rcb8 51. Qb2 Qg8 52. Qa2 Qh7 53. R1b2 Ra8 54. Qb1 Rab8 55. Kf1 Ng8 56. Be2 Ne7 57. Kf2 f6 58. Kg1 Ng6 59. Nxg6 Qxg6 60. Ra3 Rg8 61. g3 Nc8 62. Rab3 Bd7 63. Bf1 Re8 64. Kh1 Rb8 65. Be2 Qf5 66. Kg1 Rb7 67. Bf1 Qg4 68. Be2 Qf5 69. Bf1 Qg4 70. Be2 Qg6 71. Kf2 Rb8 72. Ke1 Rg8 73. Bf1 Re8 74. Bg2 Bf5 75. Rb5 Ra8 76. Rf2 Ra6 77. Ke2 Ne7 78. Rb3 Bd7 79. Bxe4 f5 80. Bf3 Bxa4 81. Ra3 Bd7 82. Kf1 Ng8 83. Qe1 Nf6 84. Rb2 Ne4 85. Kg2 Rg8 86. Kf1 Raa8 87. Kg2 Ra7 88. Rab3 Rb7 89. Ra3 Rbb8 90. Qa1 Ra8 91. Qe1 a4 92. Be2 Qf7 93. Bf3 Qf6 94. Kh3 Qg6 95. Kg2 Ra5 96. Rba2 Ra7 97. Be2 Raa8 98. Rb2 Qg7 99. Bf3 Qh8 100. Kh1 Qh7 101. Be2 Be8 102. Bd3 Qg6 103. Rg2 Bd7 104. Bg1 Nf6 105. Be2 Rgb8 106. Qc1 Re8 107. Bf3 Re4 108. Bxe4 Nxe4 109. Kh2 Qg4 110. Qc2 Nf6 111. Rf2 Kb7 112. Ra1 Ne4 113. Rg2 Qf3 114. Rb1 Nf6 115. Qb2 Ra6 116. Qc2 Ng4+ 117. Kh1 Nf6 118. Ra1 Kc7 119. Kh2 Ra8 120. Rb1 Re8 121. Qb2 Rb8 122. Qc2 Re8 123. Qb2 Ng4+ 124. Kh1 Rb8 125. Qc2 Ra8 126. Ra1 Kb7 127. Rb1 a3 128. Qb3 Ra6 129. Qc2 Kc7 130. Ra1 Bc8 131. Qb1 Ra5 132. Qc2 Ra8 133. Qb1 Nf6 134. Kh2 Ng4+ 135. Kh1 Nf6 136. Kh2 Ra5 137. Qc2 Ra6 138. Qb1 Ng4+ 139. Kh1 Nf6 140. Kh2 Ra8 {3-fold repetition} 141. Qb5 Bb7 142. Qb1 Bc8 {3-fold repetition} 143. Kh1 {3-fold repetition} Ra5 144. Qd3 Ne4 145. Kh2 Ba6 146. Raa2 Kb8 147. Bf2 Nf6 148. g4 Nxg4+ 149. Kh1 Qe4 150. Qxe4 fxe4 151. Rxg4 hxg4 152. h5 Bxc4 153. h6 Ra7 154. Rxa3 Rh7 155. Kg2 Rxh6 156. Ra1 Kb7 157. f5 Rf6 158. Bg3 Rxf5 159. Bxd6 Rxd5 160. Bf4 Be2 161. Kg3 Bf3 162. c4 Rd2 163. Rc1 Rb2 164. Be5 Ra2 165. Kf4 Kc6 166. Kf5 Ra4 167. Rc2 Bd1 168. Rd2 Bb3 169. Rd6+ Kb7 170. Kxg4 Bxc4 171. Rd7+ Ka6 172. Kf4 Bd3 173. Bf6 Ra3 174. Rc7 Rb3 175. Ke5 Bc2 176. Kf4 Rd3 177. Rc6 Kb5 178. Re6 Rd5 179. Be5 Rd7 180. Rh6 Rb7 181. Rh2 Bd3 182. Kf5 Kc4 183. Ke6 b5 184. Kd6 b4 185. Rb2 Rb6+ 186. Kd7 Ra6 187. Rg2 Kb5 188. Rh2 Rg6 189. Ke7 c4 190. Rh5 Ka4 191. Rh1 c3 192. Kf7 0-1 [/pgn]

25. ....g3!!! Sacrifice a pawn to open "g"file.
78.....Bd7 (sacrifice center pawn to open "e" file.
107....Re4!!! Sacrifice a rook! Leela see a knight a center is better than a rook, so sacrificed a rook and keep her knight.

From Stockfish POV, Stockfish also sacrificed a knight in the centre, in exchange for two centre pawn, but Leela did not take the knight

Thanks for this game. Strange how SF didn't claim (at moves 140, 142 and 143) a three-fold repetition as pointed out (see game comment) above. There were three opportunities to claim for a draw and yet SF didn't do it. Maybe SF felt it is winning due to material advantage. Conversely, Lc0 should have avoided those repetitions if it (Lc0) knew it was winning. Would be nice to see the logs if indeed both of them were thinking they were winning. But if SF did indeed consider it was losing at that point (move 140) then the correct move is to just claim a draw via a three-fold-repetition.

Both conditions should be met to prove that both Stockfish 18122721 and LCZero v20-rc2-32329 don't have a 3-fold repetition blindness (bug).
-SF thought it was winning (SO NO DRAW CLAIM) and also Lc0 v20 32329 thought it was just drawish game (hence it allowed 3-fold repetition many times) so it reached up to move 192.

[Guenther]

Capture 6.PNGCapture 5.PNGcap4.png[pgn][Event "Lc0 T35 vs SFDev (2x2070 vs TR1-12c)"] [Site "?"] [Date "2019.01.01"] [Round "57.1"] [White "Stockfish 18122721"] [Black "LCZero v20-rc2-32329"] [Result "0-1"] [BlackElo "3247"] [ECO "E31"] [Opening "Nimzo-Indian"] [Variation "Leningrad, Main Line, 8...e5 9.Qc2"] [WhiteElo "3519"] [TimeControl "1200+2"] [Termination "normal"] [PlyCount "383"] [WhiteType "human"] [BlackType "human"] 1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. Bg5 h6 5. Bh4 c5 6. d5 Bxc3+ 7. bxc3 d6 8. e3 e5 9. Qc2 Qe7 10. Nf3 Nbd7 11. Nd2 Kd8 12. f3 g5 13. Bg3 Nb6 14. Bd3 h5 15. h3 Rg8 16. a4 a5 17. h4 g4 18. Qb1 Kc7 19. f4 e4 20. Bc2 Bf5 21. O-O Nc8 22. Qb5 Re8 23. Ra2 Ng8 24. Qb1 Nh6 25. Bf2 g3 26. Bxg3 Ng4 27. Re1 b6 28. Bd1 Nf6 29. Nf3 Qf8 30. Ne5 Qg8 31. Bh2 Qh7 32. Ra3 Rg8 33. Rf1 Rf8 34. Qb5 Na7 35. Qb2 Qg7 36. Rf2 Rfd8 37. Rb3 Nc8 38. Qb1 Ra6 39. Rbb2 Ra8 40. Rbd2 Rg8 41. Qb5 Na7 42. Qb3 Qh7 43. Rb2 Rgb8 44. Be2 Rb7 45. Rf1 Qg7 46. Rfb1 Rg8 47. Bd1 Rf8 48. Qc2 Qh7 49. Qf2 Rc8 50. Rb3 Rcb8 51. Qb2 Qg8 52. Qa2 Qh7 53. R1b2 Ra8 54. Qb1 Rab8 55. Kf1 Ng8 56. Be2 Ne7 57. Kf2 f6 58. Kg1 Ng6 59. Nxg6 Qxg6 60. Ra3 Rg8 61. g3 Nc8 62. Rab3 Bd7 63. Bf1 Re8 64. Kh1 Rb8 65. Be2 Qf5 66. Kg1 Rb7 67. Bf1 Qg4 68. Be2 Qf5 69. Bf1 Qg4 70. Be2 Qg6 71. Kf2 Rb8 72. Ke1 Rg8 73. Bf1 Re8 74. Bg2 Bf5 75. Rb5 Ra8 76. Rf2 Ra6 77. Ke2 Ne7 78. Rb3 Bd7 79. Bxe4 f5 80. Bf3 Bxa4 81. Ra3 Bd7 82. Kf1 Ng8 83. Qe1 Nf6 84. Rb2 Ne4 85. Kg2 Rg8 86. Kf1 Raa8 87. Kg2 Ra7 88. Rab3 Rb7 89. Ra3 Rbb8 90. Qa1 Ra8 91. Qe1 a4 92. Be2 Qf7 93. Bf3 Qf6 94. Kh3 Qg6 95. Kg2 Ra5 96. Rba2 Ra7 97. Be2 Raa8 98. Rb2 Qg7 99. Bf3 Qh8 100. Kh1 Qh7 101. Be2 Be8 102. Bd3 Qg6 103. Rg2 Bd7 104. Bg1 Nf6 105. Be2 Rgb8 106. Qc1 Re8 107. Bf3 Re4 108. Bxe4 Nxe4 109. Kh2 Qg4 110. Qc2 Nf6 111. Rf2 Kb7 112. Ra1 Ne4 113. Rg2 Qf3 114. Rb1 Nf6 115. Qb2 Ra6 116. Qc2 Ng4+ 117. Kh1 Nf6 118. Ra1 Kc7 119. Kh2 Ra8 120. Rb1 Re8 121. Qb2 Rb8 122. Qc2 Re8 123. Qb2 Ng4+ 124. Kh1 Rb8 125. Qc2 Ra8 126. Ra1 Kb7 127. Rb1 a3 128. Qb3 Ra6 129. Qc2 Kc7 130. Ra1 Bc8 131. Qb1 Ra5 132. Qc2 Ra8 133. Qb1 Nf6 134. Kh2 Ng4+ 135. Kh1 Nf6 136. Kh2 Ra5 137. Qc2 Ra6 138. Qb1 Ng4+ 139. Kh1 Nf6 140. Kh2 Ra8 {3-fold repetition} 141. Qb5 Bb7 142. Qb1 Bc8 {3-fold repetition} 143. Kh1 {3-fold repetition} Ra5 144. Qd3 Ne4 145. Kh2 Ba6 146. Raa2 Kb8 147. Bf2 Nf6 148. g4 Nxg4+ 149. Kh1 Qe4 150. Qxe4 fxe4 151. Rxg4 hxg4 152. h5 Bxc4 153. h6 Ra7 154. Rxa3 Rh7 155. Kg2 Rxh6 156. Ra1 Kb7 157. f5 Rf6 158. Bg3 Rxf5 159. Bxd6 Rxd5 160. Bf4 Be2 161. Kg3 Bf3 162. c4 Rd2 163. Rc1 Rb2 164. Be5 Ra2 165. Kf4 Kc6 166. Kf5 Ra4 167. Rc2 Bd1 168. Rd2 Bb3 169. Rd6+ Kb7 170. Kxg4 Bxc4 171. Rd7+ Ka6 172. Kf4 Bd3 173. Bf6 Ra3 174. Rc7 Rb3 175. Ke5 Bc2 176. Kf4 Rd3 177. Rc6 Kb5 178. Re6 Rd5 179. Be5 Rd7 180. Rh6 Rb7 181. Rh2 Bd3 182. Kf5 Kc4 183. Ke6 b5 184. Kd6 b4 185. Rb2 Rb6+ 186. Kd7 Ra6 187. Rg2 Kb5 188. Rh2 Rg6 189. Ke7 c4 190. Rh5 Ka4 191. Rh1 c3 192. Kf7 0-1 [/pgn]

25. ....g3!!! Sacrifice a pawn to open "g"file.
78.....Bd7 (sacrifice center pawn to open "e" file.
107....Re4!!! Sacrifice a rook! Leela see a knight a center is better than a rook, so sacrificed a rook and keep her knight.

From Stockfish POV, Stockfish also sacrificed a knight in the centre, in exchange for two centre pawn, but Leela did not take the knight

Thanks for this game. Strange how SF didn't claim (at moves 140, 142 and 143) a three-fold repetition as pointed out (see game comment) above. There were three opportunities to claim for a draw and yet SF didn't do it. Maybe SF felt it is winning due to material advantage. Conversely, Lc0 should have avoided those repetitions if it (Lc0) knew it was winning. Would be nice to see the logs if indeed both of them were thinking they were winning. But if SF did indeed consider it was losing at that point (move 140) then the correct move is to just claim a draw via a three-fold-repetition.

Both conditions should be met to prove that both Stockfish 18122721 and LCZero v20-rc2-32329 don't have a 3-fold repetition blindness (bug).
-SF thought it was winning (SO NO DRAW CLAIM) and also Lc0 v20 32329 thought it was just drawish game (hence it allowed 3-fold repetition many times) so it reached up to move 192.

Sorry, all your speculations about bugs and 3-fold are obsolete.

The OP just used a GUI, which doesn't know the complete chess rules (e.g. Arena - it does not consider the right to move! for 3-fold and always adds faulty 'repetitions' to the pgns).
This happens already a few times per month now (posts with wrong 3-fold claims), since LC0 loves shuffling
and users love Arena. (just search for wrong repetition...)

a few examples:
viewtopic.php?f=6&t=69191&p=781900&hili ... ng#p781900
viewtopic.php?f=2&t=68417&p=773571&hili ... ng#p773571
viewtopic.php?f=2&t=66202&p=745941&hili ... ng#p745941

[Nay Lin Tun]

SF claimed white is better since the opening and about half of the whole game, meanwhile LCo think black is better since the end of book move!
It was a really tense and confusing game! See the evaluation graph in the middle.
The question become "Why Lco think black is better" since the beginning whereas SF disagreed!
People were mad whose evaluation to be trusted!

phpJGWomv.jpeg

[MikeGL]

Capture 6.PNGCapture 5.PNGcap4.png[pgn][Event "Lc0 T35 vs SFDev (2x2070 vs TR1-12c)"] [Site "?"] [Date "2019.01.01"] [Round "57.1"] [White "Stockfish 18122721"] [Black "LCZero v20-rc2-32329"] [Result "0-1"] [BlackElo "3247"] [ECO "E31"] [Opening "Nimzo-Indian"] [Variation "Leningrad, Main Line, 8...e5 9.Qc2"] [WhiteElo "3519"] [TimeControl "1200+2"] [Termination "normal"] [PlyCount "383"] [WhiteType "human"] [BlackType "human"] 1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. Bg5 h6 5. Bh4 c5 6. d5 Bxc3+ 7. bxc3 d6 8. e3 e5 9. Qc2 Qe7 10. Nf3 Nbd7 11. Nd2 Kd8 12. f3 g5 13. Bg3 Nb6 14. Bd3 h5 15. h3 Rg8 16. a4 a5 17. h4 g4 18. Qb1 Kc7 19. f4 e4 20. Bc2 Bf5 21. O-O Nc8 22. Qb5 Re8 23. Ra2 Ng8 24. Qb1 Nh6 25. Bf2 g3 26. Bxg3 Ng4 27. Re1 b6 28. Bd1 Nf6 29. Nf3 Qf8 30. Ne5 Qg8 31. Bh2 Qh7 32. Ra3 Rg8 33. Rf1 Rf8 34. Qb5 Na7 35. Qb2 Qg7 36. Rf2 Rfd8 37. Rb3 Nc8 38. Qb1 Ra6 39. Rbb2 Ra8 40. Rbd2 Rg8 41. Qb5 Na7 42. Qb3 Qh7 43. Rb2 Rgb8 44. Be2 Rb7 45. Rf1 Qg7 46. Rfb1 Rg8 47. Bd1 Rf8 48. Qc2 Qh7 49. Qf2 Rc8 50. Rb3 Rcb8 51. Qb2 Qg8 52. Qa2 Qh7 53. R1b2 Ra8 54. Qb1 Rab8 55. Kf1 Ng8 56. Be2 Ne7 57. Kf2 f6 58. Kg1 Ng6 59. Nxg6 Qxg6 60. Ra3 Rg8 61. g3 Nc8 62. Rab3 Bd7 63. Bf1 Re8 64. Kh1 Rb8 65. Be2 Qf5 66. Kg1 Rb7 67. Bf1 Qg4 68. Be2 Qf5 69. Bf1 Qg4 70. Be2 Qg6 71. Kf2 Rb8 72. Ke1 Rg8 73. Bf1 Re8 74. Bg2 Bf5 75. Rb5 Ra8 76. Rf2 Ra6 77. Ke2 Ne7 78. Rb3 Bd7 79. Bxe4 f5 80. Bf3 Bxa4 81. Ra3 Bd7 82. Kf1 Ng8 83. Qe1 Nf6 84. Rb2 Ne4 85. Kg2 Rg8 86. Kf1 Raa8 87. Kg2 Ra7 88. Rab3 Rb7 89. Ra3 Rbb8 90. Qa1 Ra8 91. Qe1 a4 92. Be2 Qf7 93. Bf3 Qf6 94. Kh3 Qg6 95. Kg2 Ra5 96. Rba2 Ra7 97. Be2 Raa8 98. Rb2 Qg7 99. Bf3 Qh8 100. Kh1 Qh7 101. Be2 Be8 102. Bd3 Qg6 103. Rg2 Bd7 104. Bg1 Nf6 105. Be2 Rgb8 106. Qc1 Re8 107. Bf3 Re4 108. Bxe4 Nxe4 109. Kh2 Qg4 110. Qc2 Nf6 111. Rf2 Kb7 112. Ra1 Ne4 113. Rg2 Qf3 114. Rb1 Nf6 115. Qb2 Ra6 116. Qc2 Ng4+ 117. Kh1 Nf6 118. Ra1 Kc7 119. Kh2 Ra8 120. Rb1 Re8 121. Qb2 Rb8 122. Qc2 Re8 123. Qb2 Ng4+ 124. Kh1 Rb8 125. Qc2 Ra8 126. Ra1 Kb7 127. Rb1 a3 128. Qb3 Ra6 129. Qc2 Kc7 130. Ra1 Bc8 131. Qb1 Ra5 132. Qc2 Ra8 133. Qb1 Nf6 134. Kh2 Ng4+ 135. Kh1 Nf6 136. Kh2 Ra5 137. Qc2 Ra6 138. Qb1 Ng4+ 139. Kh1 Nf6 140. Kh2 Ra8 {3-fold repetition} 141. Qb5 Bb7 142. Qb1 Bc8 {3-fold repetition} 143. Kh1 {3-fold repetition} Ra5 144. Qd3 Ne4 145. Kh2 Ba6 146. Raa2 Kb8 147. Bf2 Nf6 148. g4 Nxg4+ 149. Kh1 Qe4 150. Qxe4 fxe4 151. Rxg4 hxg4 152. h5 Bxc4 153. h6 Ra7 154. Rxa3 Rh7 155. Kg2 Rxh6 156. Ra1 Kb7 157. f5 Rf6 158. Bg3 Rxf5 159. Bxd6 Rxd5 160. Bf4 Be2 161. Kg3 Bf3 162. c4 Rd2 163. Rc1 Rb2 164. Be5 Ra2 165. Kf4 Kc6 166. Kf5 Ra4 167. Rc2 Bd1 168. Rd2 Bb3 169. Rd6+ Kb7 170. Kxg4 Bxc4 171. Rd7+ Ka6 172. Kf4 Bd3 173. Bf6 Ra3 174. Rc7 Rb3 175. Ke5 Bc2 176. Kf4 Rd3 177. Rc6 Kb5 178. Re6 Rd5 179. Be5 Rd7 180. Rh6 Rb7 181. Rh2 Bd3 182. Kf5 Kc4 183. Ke6 b5 184. Kd6 b4 185. Rb2 Rb6+ 186. Kd7 Ra6 187. Rg2 Kb5 188. Rh2 Rg6 189. Ke7 c4 190. Rh5 Ka4 191. Rh1 c3 192. Kf7 0-1 [/pgn]

25. ....g3!!! Sacrifice a pawn to open "g"file.
78.....Bd7 (sacrifice center pawn to open "e" file.
107....Re4!!! Sacrifice a rook! Leela see a knight a center is better than a rook, so sacrificed a rook and keep her knight.

From Stockfish POV, Stockfish also sacrificed a knight in the centre, in exchange for two centre pawn, but Leela did not take the knight

Thanks for this game. Strange how SF didn't claim (at moves 140, 142 and 143) a three-fold repetition as pointed out (see game comment) above. There were three opportunities to claim for a draw and yet SF didn't do it. Maybe SF felt it is winning due to material advantage. Conversely, Lc0 should have avoided those repetitions if it (Lc0) knew it was winning. Would be nice to see the logs if indeed both of them were thinking they were winning. But if SF did indeed consider it was losing at that point (move 140) then the correct move is to just claim a draw via a three-fold-repetition.

Both conditions should be met to prove that both Stockfish 18122721 and LCZero v20-rc2-32329 don't have a 3-fold repetition blindness (bug).
-SF thought it was winning (SO NO DRAW CLAIM) and also Lc0 v20 32329 thought it was just drawish game (hence it allowed 3-fold repetition many times) so it reached up to move 192.

Sorry, all your speculations about bugs and 3-fold are obsolete.

The OP just used a GUI, which doesn't know the complete chess rules (e.g. Arena - it does not consider the right to move! for 3-fold and always adds faulty 'repetitions' to the pgns).
This happens already a few times per month now (posts with wrong 3-fold claims), since LC0 loves shuffling
and users love Arena. (just search for wrong repetition...)

a few examples:
viewtopic.php?f=6&t=69191&p=781900&hili ... ng#p781900
viewtopic.php?f=2&t=68417&p=773571&hili ... ng#p773571
viewtopic.php?f=2&t=66202&p=745941&hili ... ng#p745941

Thanks a lot for the reply. I rechecked the positions and you are indeed right, the side to move was different though the position was the same. So the Arena bug you mention is correct. Sorry, missed the memo. Strange how this old bug of Arena was not fixed.

Happy new year and thanks again for the clarification.

[MikeB]

Capture 6.PNGCapture 5.PNGcap4.png[pgn][Event "Lc0 T35 vs SFDev (2x2070 vs TR1-12c)"] [Site "?"] [Date "2019.01.01"] [Round "57.1"] [White "Stockfish 18122721"] [Black "LCZero v20-rc2-32329"] [Result "0-1"] [BlackElo "3247"] [ECO "E31"] [Opening "Nimzo-Indian"] [Variation "Leningrad, Main Line, 8...e5 9.Qc2"] [WhiteElo "3519"] [TimeControl "1200+2"] [Termination "normal"] [PlyCount "383"] [WhiteType "human"] [BlackType "human"] 1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. Bg5 h6 5. Bh4 c5 6. d5 Bxc3+ 7. bxc3 d6 8. e3 e5 9. Qc2 Qe7 10. Nf3 Nbd7 11. Nd2 Kd8 12. f3 g5 13. Bg3 Nb6 14. Bd3 h5 15. h3 Rg8 16. a4 a5 17. h4 g4 18. Qb1 Kc7 19. f4 e4 20. Bc2 Bf5 21. O-O Nc8 22. Qb5 Re8 23. Ra2 Ng8 24. Qb1 Nh6 25. Bf2 g3 26. Bxg3 Ng4 27. Re1 b6 28. Bd1 Nf6 29. Nf3 Qf8 30. Ne5 Qg8 31. Bh2 Qh7 32. Ra3 Rg8 33. Rf1 Rf8 34. Qb5 Na7 35. Qb2 Qg7 36. Rf2 Rfd8 37. Rb3 Nc8 38. Qb1 Ra6 39. Rbb2 Ra8 40. Rbd2 Rg8 41. Qb5 Na7 42. Qb3 Qh7 43. Rb2 Rgb8 44. Be2 Rb7 45. Rf1 Qg7 46. Rfb1 Rg8 47. Bd1 Rf8 48. Qc2 Qh7 49. Qf2 Rc8 50. Rb3 Rcb8 51. Qb2 Qg8 52. Qa2 Qh7 53. R1b2 Ra8 54. Qb1 Rab8 55. Kf1 Ng8 56. Be2 Ne7 57. Kf2 f6 58. Kg1 Ng6 59. Nxg6 Qxg6 60. Ra3 Rg8 61. g3 Nc8 62. Rab3 Bd7 63. Bf1 Re8 64. Kh1 Rb8 65. Be2 Qf5 66. Kg1 Rb7 67. Bf1 Qg4 68. Be2 Qf5 69. Bf1 Qg4 70. Be2 Qg6 71. Kf2 Rb8 72. Ke1 Rg8 73. Bf1 Re8 74. Bg2 Bf5 75. Rb5 Ra8 76. Rf2 Ra6 77. Ke2 Ne7 78. Rb3 Bd7 79. Bxe4 f5 80. Bf3 Bxa4 81. Ra3 Bd7 82. Kf1 Ng8 83. Qe1 Nf6 84. Rb2 Ne4 85. Kg2 Rg8 86. Kf1 Raa8 87. Kg2 Ra7 88. Rab3 Rb7 89. Ra3 Rbb8 90. Qa1 Ra8 91. Qe1 a4 92. Be2 Qf7 93. Bf3 Qf6 94. Kh3 Qg6 95. Kg2 Ra5 96. Rba2 Ra7 97. Be2 Raa8 98. Rb2 Qg7 99. Bf3 Qh8 100. Kh1 Qh7 101. Be2 Be8 102. Bd3 Qg6 103. Rg2 Bd7 104. Bg1 Nf6 105. Be2 Rgb8 106. Qc1 Re8 107. Bf3 Re4 108. Bxe4 Nxe4 109. Kh2 Qg4 110. Qc2 Nf6 111. Rf2 Kb7 112. Ra1 Ne4 113. Rg2 Qf3 114. Rb1 Nf6 115. Qb2 Ra6 116. Qc2 Ng4+ 117. Kh1 Nf6 118. Ra1 Kc7 119. Kh2 Ra8 120. Rb1 Re8 121. Qb2 Rb8 122. Qc2 Re8 123. Qb2 Ng4+ 124. Kh1 Rb8 125. Qc2 Ra8 126. Ra1 Kb7 127. Rb1 a3 128. Qb3 Ra6 129. Qc2 Kc7 130. Ra1 Bc8 131. Qb1 Ra5 132. Qc2 Ra8 133. Qb1 Nf6 134. Kh2 Ng4+ 135. Kh1 Nf6 136. Kh2 Ra5 137. Qc2 Ra6 138. Qb1 Ng4+ 139. Kh1 Nf6 140. Kh2 Ra8 {3-fold repetition} 141. Qb5 Bb7 142. Qb1 Bc8 {3-fold repetition} 143. Kh1 {3-fold repetition} Ra5 144. Qd3 Ne4 145. Kh2 Ba6 146. Raa2 Kb8 147. Bf2 Nf6 148. g4 Nxg4+ 149. Kh1 Qe4 150. Qxe4 fxe4 151. Rxg4 hxg4 152. h5 Bxc4 153. h6 Ra7 154. Rxa3 Rh7 155. Kg2 Rxh6 156. Ra1 Kb7 157. f5 Rf6 158. Bg3 Rxf5 159. Bxd6 Rxd5 160. Bf4 Be2 161. Kg3 Bf3 162. c4 Rd2 163. Rc1 Rb2 164. Be5 Ra2 165. Kf4 Kc6 166. Kf5 Ra4 167. Rc2 Bd1 168. Rd2 Bb3 169. Rd6+ Kb7 170. Kxg4 Bxc4 171. Rd7+ Ka6 172. Kf4 Bd3 173. Bf6 Ra3 174. Rc7 Rb3 175. Ke5 Bc2 176. Kf4 Rd3 177. Rc6 Kb5 178. Re6 Rd5 179. Be5 Rd7 180. Rh6 Rb7 181. Rh2 Bd3 182. Kf5 Kc4 183. Ke6 b5 184. Kd6 b4 185. Rb2 Rb6+ 186. Kd7 Ra6 187. Rg2 Kb5 188. Rh2 Rg6 189. Ke7 c4 190. Rh5 Ka4 191. Rh1 c3 192. Kf7 0-1 [/pgn]

25. ....g3!!! Sacrifice a pawn to open "g"file.
78.....Bd7 (sacrifice center pawn to open "e" file.
107....Re4!!! Sacrifice a rook! Leela see a knight a center is better than a rook, so sacrificed a rook and keep her knight.

From Stockfish POV, Stockfish also sacrificed a knight in the centre, in exchange for two centre pawn, but Leela did not take the knight

Thanks for this game. Strange how SF didn't claim (at moves 140, 142 and 143) a three-fold repetition as pointed out (see game comment) above. There were three opportunities to claim for a draw and yet SF didn't do it. Maybe SF felt it is winning due to material advantage. Conversely, Lc0 should have avoided those repetitions if it (Lc0) knew it was winning. Would be nice to see the logs if indeed both of them were thinking they were winning. But if SF did indeed consider it was losing at that point (move 140) then the correct move is to just claim a draw via a three-fold-repetition.

Both conditions should be met to prove that both Stockfish 18122721 and LCZero v20-rc2-32329 don't have a 3-fold repetition blindness (bug).
-SF thought it was winning (SO NO DRAW CLAIM) and also Lc0 v20 32329 thought it was just drawish game (hence it allowed 3-fold repetition many times) so it reached up to move 192.

There is no code in SF that sends a draw claim to the GUI. It assumes the GUI will handle those cases appropriately. The UCI protocol calls for the GUI to act as arbiter and declare a game drawn after a threefold repetition has occurred. The GUI used in the games above is either not fully UCI compliant or perhaps some setting was not set properly. I use xBoard and one may set various adjudications settings, including 3 fold.

[MikeGL]

Capture 6.PNGCapture 5.PNGcap4.png[pgn][Event "Lc0 T35 vs SFDev (2x2070 vs TR1-12c)"] [Site "?"] [Date "2019.01.01"] [Round "57.1"] [White "Stockfish 18122721"] [Black "LCZero v20-rc2-32329"] [Result "0-1"] [BlackElo "3247"] [ECO "E31"] [Opening "Nimzo-Indian"] [Variation "Leningrad, Main Line, 8...e5 9.Qc2"] [WhiteElo "3519"] [TimeControl "1200+2"] [Termination "normal"] [PlyCount "383"] [WhiteType "human"] [BlackType "human"] 1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. Bg5 h6 5. Bh4 c5 6. d5 Bxc3+ 7. bxc3 d6 8. e3 e5 9. Qc2 Qe7 10. Nf3 Nbd7 11. Nd2 Kd8 12. f3 g5 13. Bg3 Nb6 14. Bd3 h5 15. h3 Rg8 16. a4 a5 17. h4 g4 18. Qb1 Kc7 19. f4 e4 20. Bc2 Bf5 21. O-O Nc8 22. Qb5 Re8 23. Ra2 Ng8 24. Qb1 Nh6 25. Bf2 g3 26. Bxg3 Ng4 27. Re1 b6 28. Bd1 Nf6 29. Nf3 Qf8 30. Ne5 Qg8 31. Bh2 Qh7 32. Ra3 Rg8 33. Rf1 Rf8 34. Qb5 Na7 35. Qb2 Qg7 36. Rf2 Rfd8 37. Rb3 Nc8 38. Qb1 Ra6 39. Rbb2 Ra8 40. Rbd2 Rg8 41. Qb5 Na7 42. Qb3 Qh7 43. Rb2 Rgb8 44. Be2 Rb7 45. Rf1 Qg7 46. Rfb1 Rg8 47. Bd1 Rf8 48. Qc2 Qh7 49. Qf2 Rc8 50. Rb3 Rcb8 51. Qb2 Qg8 52. Qa2 Qh7 53. R1b2 Ra8 54. Qb1 Rab8 55. Kf1 Ng8 56. Be2 Ne7 57. Kf2 f6 58. Kg1 Ng6 59. Nxg6 Qxg6 60. Ra3 Rg8 61. g3 Nc8 62. Rab3 Bd7 63. Bf1 Re8 64. Kh1 Rb8 65. Be2 Qf5 66. Kg1 Rb7 67. Bf1 Qg4 68. Be2 Qf5 69. Bf1 Qg4 70. Be2 Qg6 71. Kf2 Rb8 72. Ke1 Rg8 73. Bf1 Re8 74. Bg2 Bf5 75. Rb5 Ra8 76. Rf2 Ra6 77. Ke2 Ne7 78. Rb3 Bd7 79. Bxe4 f5 80. Bf3 Bxa4 81. Ra3 Bd7 82. Kf1 Ng8 83. Qe1 Nf6 84. Rb2 Ne4 85. Kg2 Rg8 86. Kf1 Raa8 87. Kg2 Ra7 88. Rab3 Rb7 89. Ra3 Rbb8 90. Qa1 Ra8 91. Qe1 a4 92. Be2 Qf7 93. Bf3 Qf6 94. Kh3 Qg6 95. Kg2 Ra5 96. Rba2 Ra7 97. Be2 Raa8 98. Rb2 Qg7 99. Bf3 Qh8 100. Kh1 Qh7 101. Be2 Be8 102. Bd3 Qg6 103. Rg2 Bd7 104. Bg1 Nf6 105. Be2 Rgb8 106. Qc1 Re8 107. Bf3 Re4 108. Bxe4 Nxe4 109. Kh2 Qg4 110. Qc2 Nf6 111. Rf2 Kb7 112. Ra1 Ne4 113. Rg2 Qf3 114. Rb1 Nf6 115. Qb2 Ra6 116. Qc2 Ng4+ 117. Kh1 Nf6 118. Ra1 Kc7 119. Kh2 Ra8 120. Rb1 Re8 121. Qb2 Rb8 122. Qc2 Re8 123. Qb2 Ng4+ 124. Kh1 Rb8 125. Qc2 Ra8 126. Ra1 Kb7 127. Rb1 a3 128. Qb3 Ra6 129. Qc2 Kc7 130. Ra1 Bc8 131. Qb1 Ra5 132. Qc2 Ra8 133. Qb1 Nf6 134. Kh2 Ng4+ 135. Kh1 Nf6 136. Kh2 Ra5 137. Qc2 Ra6 138. Qb1 Ng4+ 139. Kh1 Nf6 140. Kh2 Ra8 {3-fold repetition} 141. Qb5 Bb7 142. Qb1 Bc8 {3-fold repetition} 143. Kh1 {3-fold repetition} Ra5 144. Qd3 Ne4 145. Kh2 Ba6 146. Raa2 Kb8 147. Bf2 Nf6 148. g4 Nxg4+ 149. Kh1 Qe4 150. Qxe4 fxe4 151. Rxg4 hxg4 152. h5 Bxc4 153. h6 Ra7 154. Rxa3 Rh7 155. Kg2 Rxh6 156. Ra1 Kb7 157. f5 Rf6 158. Bg3 Rxf5 159. Bxd6 Rxd5 160. Bf4 Be2 161. Kg3 Bf3 162. c4 Rd2 163. Rc1 Rb2 164. Be5 Ra2 165. Kf4 Kc6 166. Kf5 Ra4 167. Rc2 Bd1 168. Rd2 Bb3 169. Rd6+ Kb7 170. Kxg4 Bxc4 171. Rd7+ Ka6 172. Kf4 Bd3 173. Bf6 Ra3 174. Rc7 Rb3 175. Ke5 Bc2 176. Kf4 Rd3 177. Rc6 Kb5 178. Re6 Rd5 179. Be5 Rd7 180. Rh6 Rb7 181. Rh2 Bd3 182. Kf5 Kc4 183. Ke6 b5 184. Kd6 b4 185. Rb2 Rb6+ 186. Kd7 Ra6 187. Rg2 Kb5 188. Rh2 Rg6 189. Ke7 c4 190. Rh5 Ka4 191. Rh1 c3 192. Kf7 0-1 [/pgn]

25. ....g3!!! Sacrifice a pawn to open "g"file.
78.....Bd7 (sacrifice center pawn to open "e" file.
107....Re4!!! Sacrifice a rook! Leela see a knight a center is better than a rook, so sacrificed a rook and keep her knight.

From Stockfish POV, Stockfish also sacrificed a knight in the centre, in exchange for two centre pawn, but Leela did not take the knight

Thanks for this game. Strange how SF didn't claim (at moves 140, 142 and 143) a three-fold repetition as pointed out (see game comment) above. There were three opportunities to claim for a draw and yet SF didn't do it. Maybe SF felt it is winning due to material advantage. Conversely, Lc0 should have avoided those repetitions if it (Lc0) knew it was winning. Would be nice to see the logs if indeed both of them were thinking they were winning. But if SF did indeed consider it was losing at that point (move 140) then the correct move is to just claim a draw via a three-fold-repetition.

Both conditions should be met to prove that both Stockfish 18122721 and LCZero v20-rc2-32329 don't have a 3-fold repetition blindness (bug).
-SF thought it was winning (SO NO DRAW CLAIM) and also Lc0 v20 32329 thought it was just drawish game (hence it allowed 3-fold repetition many times) so it reached up to move 192.

There is no code in SF that sends a draw claim to the GUI. It assumes the GUI will handle those cases appropriately. The UCI protocol calls for the GUI to act as arbiter and declare a game drawn after a threefold repetition has occurred. The GUI used in the games above is either not fully UCI compliant or perhaps some setting was not set properly. I use xBoard and one may set various adjudications settings, including 3 fold.

Thanks for that info. Major difference in human-human chess. Where it is up to players to detect a 3-fold and mutually agree for a draw, or if the opposing player won't accept, then you call the arbiter to prove that 3-fold did indeed occur, else if nobody notices the 3-fold then the game continues and won't be stopped by arbiter nor by DGT board.