How To Draw Your Won Game

Just push that pawn at the wrong time as Black did here at move 84.  There's a reason to study endgames, eh?

[Event "Qatar Masters Open 2015"]
[Site "Doha"]
[Date "2015.12.28"]
[Round "8"]
[White "Abhishek, Kelkar"]
[Black "Krush, Irina"]
[Result "1/2-1/2"]
[ECO "B32"]
[WhiteElo "2393"]
[BlackElo "2468"]
[PlyCount "170"]
[EventDate "2015.??.??"]
[EventCountry "QAT"]
[TimeControl "40/5400+30:1800+30"]

1. e4 {0} c5 {13} 2. Nf3 {0} Nc6 {35} 3. d4 {47} cxd4 {15} 4. Nxd4 {4} e5 {36}
5. Nb5 {83} d6 {10} 6. c4 {84} a6 {29} 7. N5c3 {94} Be7 {25} 8. Bd3 {61} Bg5 {
36} 9. Nd2 {162} Nge7 {79} 10. O-O {194} O-O {51} 11. Nb3 {38} Bxc1 {41} 12.
Rxc1 {6} Be6 {353} 13. Qd2 {119} Na5 {307} 14. Nd5 {563} Nec6 {645} 15. Bb1 {
316} Nxb3 {72} 16. axb3 {4} Nd4 {135} 17. Rc3 {9} Bxd5 {494} 18. exd5 {16} Qb6
{235} 19. g4 {324} f5 {368} 20. gxf5 {128} Nxf5 {10} 21. Qg5 {671} Qd8 {498}
22. Qg4 {65} Qf6 {429} 23. Kh1 {181} g6 {204} 24. Rh3 {655} Rae8 {431} 25. b4 {
165} Nd4 {373} 26. c5 {182} Re7 {310} 27. Be4 {319} Ref7 {75} 28. Rg1 {142} Rg7
{90} 29. c6 {451} Qe7 {648} 30. Rc3 {157} Qc7 {6} 31. Rf1 {563} Rgf7 {34} 32.
f3 {51} Ne2 {96} 33. Rc2 {93} Nd4 {76} 34. Rc3 {138} Ne2 {64} 35. Rc2 {11} Nd4
{68} 36. Rc4 {15} Rf4 {35} 37. Qg2 {35} R8f7 {31} 38. Rc3 {44} Kg7 {20} 39. Rg1
{56} R4f6 {32} 40. f4 {0} exf4 {0} 41. Qf2 {207} Nb5 {253} 42. Rh3 {116} Qe7 {
340} 43. Bf3 {47} Qf8 {257} 44. Bg4 {461} bxc6 {203} 45. dxc6 {148} d5 {28} 46.
Bf3 {177} Qd6 {98} 47. Rc1 {282} Rc7 {101} 48. Qh4 {93} Kh8 {254} 49. Rc5 {275}
Rf5 {473} 50. Bg4 {76} Rff7 {1} 51. Bd7 {300} Qe5 {35} 52. Qf2 {135} Qe4+ {83}
53. Kg1 {120} f3 {37} 54. Rc1 {101} Nd4 {34} 55. Re1 {19} Ne2+ {35} 56. Kh1 {41
} d4 {43} 57. Rxf3 {13} Rxf3 {41} 58. Rxe2 {9} Qd5 {40} 59. Re5 {32} Rxf2+ {69}
60. Rxd5 {9} Rd2 {24} 61. Kg1 {37} d3 {33} 62. b3 {5} Kg7 {16} 63. h3 {6} Kf6 {
14} 64. Kf1 {8} g5 {60} 65. Ke1 {16} Re2+ {21} 66. Kd1 {45} Re4 {31} 67. b5 {13
} axb5 {10} 68. Rxb5 {6} Rxd7 {48} 69. cxd7 {69} Rd4 {8} 70. Kd2 {91} Rxd7 {16}
71. Rc5 {4} h5 {32} 72. Rc3 {108} h4 {44} 73. Rxd3 {19} Rxd3+ {46} 74. Kxd3 {5}
g4 {5} 75. Ke2 {12} g3 {12} 76. Kf3 {25} Ke5 {31} 77. b4 {6} Kd5 {33} 78. b5 {
10} Kc5 {4} 79. b6 {2} Kxb6 {6} 80. Kg2 {5} Kc5 {5} 81. Kg1 {14} Kd4 {28} 82.
Kg2 {8} Ke3 {41} 83. Kg1 {18} Kf3 {53} 84. Kf1 {6} g2+ {45} 85. Kg1 {4} Kg3 {5}
1/2-1/2