For a long time I had been suffering but Black's last move (51...Rb2) allows a forced sequence of moves that leads to a draw.

51. Nc4! Rxe2+ 52. Kxe2 Nc3+ 53. Kd2 Nxd1 54. Nd6+! The pointe; otherwise White has no chance: 54. Kxd1 Ke6 55. Kd2 Kd5 56. Kc3 Kc5 and the b-pawn is lost. 54... Ke6 55. Nxe4 fxe4 56. Kxd1 Kd5 57. Ke2 Kc5 58. Ke3 Kxb5 59. g4 Kc5 60. Kxe4 Kd6 Of 60... b5 61. Ke5 b4 62. f5 is a draw. 61. Kd4 h5 62. f5! Defending passively with 62. Kc4 h4 63. Kd4 b5 64. f5 gxf5 65. gxf5 Ke7 66. Kc5 Kf6 67. Kxb5 Kxf5 68. Kc4 Ke4 69. Kc3 Kf3 70. Kd2 Kg2 71. Ke1 Kxh3 72. Kf1 works too here, but the text move accelerates the end. 62... gxf5 63. gxh5 Ke6 64. h6 Kf6 65. h7 Kg7 66. Ke5 Kh8 1/2-1/2