Glaurung uses under promotion to beat DJ Yokohama

[MikeB]

[pgn][Event "Computer Chess Game"]
[Site "iMac.local"]
[Date "2015.05.15"]
[Round "36"]
[White "Glaurung 2.2"]
[Black "Deep Junior Yokohama"]
[Result "1-0"]
[TimeControl "40/120"]
[Annotator "8. +0.23 8... -0.26"]

1. d4 Nf6 2. Nf3 g6 3. Bf4 Bg7 4. e3 d6 5. h3 O-O 6. Be2 c5 7. c3 b6 8. O-O
{+0.23/14 5} Nbd7 {-0.26/15 4} 9. Nbd2 {+0.35/14 12} Bb7 {-0.21/16 23} 10.
Rc1 {+0.35/13 13} Re8 {+0.00/14 2.6} 11. Bg5 {+0.31/13 5} h6 {-0.03/16 4}
12. Bh4 {+0.29/13 2.8} g5 {-0.04/15 7} 13. Bg3 {+0.49/14 3} e5 {-0.11/15 3}
14. Qb3 {+0.49/12 4} e4 {+0.07/14 2.2} 15. Nh2 {+0.58/15 6} d5 {+0.04/16 4}
16. Ng4 {+0.58/14 3} Nxg4 {+0.08/15 2.6} 17. Bxg4 {+0.58/14 2.2} Bc6
{+0.06/15 4} 18. Bd6 {+0.56/14 2.6} h5 {+0.08/14 1.9} 19. Bxd7 {+0.72/15 3}
Qxd7 {+0.00/15 1.6} 20. dxc5 {+0.90/15 2.5} bxc5 {-0.03/15 3} 21. Bxc5
{+0.74/15 2.8} g4 {+0.01/17 7} 22. hxg4 {+0.72/13 1.9} Qxg4 {-0.01/16 8}
23. f3 {+1.03/14 4} Qg6 {+0.07/14 7} 24. fxe4 {+1.19/14 2.3} dxe4
{+0.12/13 1.6} 25. Bd4 {+1.15/13 2.8} Rab8 {+0.08/14 3} 26. Qa3
{+1.49/14 2.8} h4 {+0.09/14 2.6} 27. Bxg7 {+1.50/13 2.2} Qxg7
{+0.05/13 1.9} 28. Rf2 {+1.33/13 2.5} Re6 {+0.00/15 6} 29. Nc4 {+1.21/13 3}
Qg3 {+0.00/15 2.7} 30. Qxa7 {+0.94/14 5} Rf8 {+0.03/13 0.9} 31. Qa5
{+0.94/13 2.8} h3 {+0.00/14 2.8} 32. Rcc2 {+1.05/13 2.1} f5 {+0.00/14 2.8}
33. Rce2 {+1.64/13 4} Bd7 {-0.21/13 1.0} 34. Rxf5 {+2.98/14 1.6} Rxf5
{-0.94/14 0.8} 35. Qxf5 {+2.92/14 0.6} Rd6 {-0.82/15 1.9} 36. Nxd6
{+2.84/14 2.9} Bxf5 {-0.73/16 4} 37. Nxf5 {+2.82/13 0.2} Qe5 {-0.73/9} 38.
Nd4 {+2.76/14 2.9} Qg3 {-0.60/6} 39. c4 {+2.43/14 2.8} Kf8 {-0.51/7} 40.
Nf5 {+2.19/16 2.6} h2+ {+0.05/3} 41. Kh1 {+3.54/12 0.4} Qe5 {-1.31/16 9}
42. Nd4 {+3.56/16 4} Ke8 {-1.31/17 2.4} 43. b3 {+3.15/16 4} Qd6
{-0.94/16 1.8} 44. Rc2 {+3.15/18 4} Qf6 {-0.83/17 5} 45. Rd2 {+2.90/16 7}
Qd6 {-0.83/16 2.1} 46. Re2 {+2.90/17 5} Qc7 {-1.11/17 5} 47. Nf5
{+3.39/17 4} Qe5 {-1.12/17 5} 48. Rf2 {+3.39/16 3} Kd7 {-1.09/17 7} 49. Nd4
{+3.11/16 5} Qg3 {-1.11/17 4} 50. Rf7+ {+2.90/15 3} Kd8 {-1.24/17 2.2} 51.
Nc6+ {+3.60/16 2.8} Kc8 {-1.11/17 3} 52. Ne7+ {+3.68/17 4} Kb8
{-1.29/17 2.3} 53. Nd5 {+3.78/17 4} Qe5 {-1.15/18 4} 54. Rf8+
{+3.82/17 2.9} Kb7 {-0.95/17 3} 55. b4 {+3.76/17 2.7} Qb2 {-0.95/17 5} 56.
Kxh2 {+3.37/17 3} Qe2 {-1.15/18 2.6} 57. Rf7+ {+3.03/17 4} Kb8
{-1.02/18 2.4} 58. Rc7 {+3.47/19 4} Qh5+ {-1.09/20 8} 59. Kg3
{+4.21/20 2.5} Qg5+ {-1.09/21 1.9} 60. Kf2 {+4.17/15 0.1} Qh4+ {-1.09/22 4}
61. Ke2 {+3.82/20 2.7} Qh1 {-1.10/22 5} 62. a4 {+3.74/18 2.0} Qxg2+
{-0.68/18 1.3} 63. Ke1 {+3.56/19 2.1} Qc2 {-0.69/20 3} 64. a5
{+3.52/19 2.3} Qa2 {-0.70/21 10} 65. Kd1 {+3.52/18 2.3} Qb1+ {-0.92/20 2.7}
66. Ke2 {+3.62/19 1.9} Qb2+ {-0.92/20 2.1} 67. Kf1 {+3.62/20 2.2} Qa2
{-0.92/20 1.0} 68. Ke1 {+3.64/19 2.8} Ka8 {-0.92/19 1.5} 69. Rd7
{+3.66/18 2.8} Kb8 {-0.95/19 4} 70. c5 {+3.82/17 3} Qb1+ {-0.95/18 1.1} 71.
Kf2 {+4.68/18 2.4} Qb2+ {-1.06/18 5} 72. Kg3 {+4.92/18 2.6} Qe5+
{-0.85/15 0.3} 73. Kh4 {+4.80/17 3} Qh2+ {-0.71/17 0.4} 74. Kg4
{+5.03/18 3} Qg2+ {-1.15/17 4} 75. Kf4 {+5.35/16 0.7} Qh2+ {-1.15/9} 76.
Kxe4 {+5.70/16 4} Qh1+ {-1.02/9} 77. Kd3 {+6.31/17 2.3} Qd1+ {-1.02/3} 78.
Kc3 {+6.15/16 0.4} Qa1+ {-1.15/8} 79. Kb3 {+6.23/18 4} Qd1+ {-1.15/7} 80.
Kb2 {+6.03/16 0.3} Qa4 {-1.15/7} 81. Rd8+ {+92.14/20 6} Kb7 {-12.15/19 8}
82. Rd6 {+99.50/22 6} Kb8 {-15.93/20 6} 83. c6 {+99.71/21 5} Ka7
{-22.11/22 10} 84. c7 {+99.73/14 0.1} Qe8 {-22.11/22 7} 85. Rd8
{+99.75/16 0.1} Qe5+ {-22.11/18 3} 86. Kb3 {+99.77/12} Qf5 {-99.82/21 9}
87. c8=N+ {+99.79/8} Ka6 {-99.80/21 3} 88. Rd6+ {+99.81/8} Kb7
{-99.82/21 2.0} 89. a6+ {+99.83/6} Ka8 {-99.82/19 4} 90. Ndb6+ {+99.85/6}
Kb8 {-99.82/9} 91. a7+ {+99.87/6} Kc7 {-99.88/20 1.9} 92. Nd5+ {+99.89/6}
Qxd5+ {-99.90/25 1.3} 93. Rxd5 {+99.91/10} Kb7 {-99.92/27 2.1} 94. Rd7+
{+99.93/8} Kc6 {-99.94/28 1.5} 95. Nb6 {+99.95/6} Kxb6 {-99.96/39 1.2} 96.
a8=Q {+99.97/6} Kb5 {-99.96/9} 97. Qb7# {+99.99/6}
{Xboard adjudication: Checkmate} 1-0[/pgn]

[d]3R4/k1P5/8/P2N1q2/1P6/1K2P3/8/8 w - - 5 87

R,B & N appear to win, but N wins fastest I believe. Obviously simple for today's engines , but a human might have missed the stalemate if it went for the Q.

[Sean Evans]

Hi, thanks for posting, I never saw an underpromotion like that one before!!

[BBauer]

R,B & N appear to win, but N wins fastest I believe. Obviously simple for today's engines , but a human might have missed the stalemate if it went for the Q.

SF would have underpromoted to rook.
That wins one move faster.

A lazy human would have played
1. Rh8+ Kxh8
2. c8Q+ Qxc8
3. Nb6+ resign
which is even faster.

Kind regards
Bernhard