Game |
| Result | Moves |
Year | Event/Locale | Opening |
51. P H Donoso Velasco vs A Martin Gonzalez |
| 1-0 | 27 | 1976 | Haifa Olympiad | B72 Sicilian, Dragon |
52. P H Donoso Velasco vs S J Hutchings |
| ½-½ | 30 | 1976 | Haifa Olympiad | B85 Sicilian, Scheveningen, Classical |
53. Keene vs P H Donoso Velasco |
  | 1-0 | 82 | 1976 | Haifa Olympiad | D35 Queen's Gambit Declined |
54. P H Donoso Velasco vs K Harandi |
| 1-0 | 48 | 1976 | Haifa Olympiad | C78 Ruy Lopez |
55. C Pesantes Carbajal vs P H Donoso Velasco |
| 1-0 | 49 | 1977 | Pan American Championship | D48 Queen's Gambit Declined Semi-Slav, Meran |
56. C Camaton Borbor vs P H Donoso Velasco |
| ½-½ | 31 | 1977 | Pan American Championship | A15 English |
57. P H Donoso Velasco vs C Escondrillas |
| ½-½ | 26 | 1977 | Pan American Championship | C48 Four Knights |
58. J Zarco Castillo vs P H Donoso Velasco |
| 0-1 | 38 | 1977 | Pan American Championship | E67 King's Indian, Fianchetto |
59. P H Donoso Velasco vs J Berry |
| 1-0 | 64 | 1977 | Pan American Championship | C60 Ruy Lopez |
60. H van Riemsdijk vs P H Donoso Velasco |
| ½-½ | 71 | 1977 | Pan American Championship | B47 Sicilian, Taimanov (Bastrikov) Variation |
61. P H Donoso Velasco vs C Gamarra Caceres |
| 1-0 | 28 | 1977 | Pan American Championship | A04 Reti Opening |
62. R Grimaldi vs P H Donoso Velasco |
| 1-0 | 29 | 1977 | Pan American Championship | B89 Sicilian |
63. P H Donoso Velasco vs A Anelli |
| ½-½ | 18 | 1977 | Pan American Championship | B32 Sicilian |
64. Denker vs P H Donoso Velasco |
| ½-½ | 67 | 1977 | Pan American Championship | E67 King's Indian, Fianchetto |
65. P H Donoso Velasco vs R Chavez Chavez |
| 1-0 | 53 | 1977 | Pan American Championship | B08 Pirc, Classical |
66. W Hook vs P H Donoso Velasco |
| 0-1 | 30 | 1977 | Pan American Championship | D10 Queen's Gambit Declined Slav |
67. P H Donoso Velasco vs J Bademian Orchanian |
| 1-0 | 65 | 1977 | Pan American Championship | C81 Ruy Lopez, Open, Howell Attack |
68. O de Leon vs P H Donoso Velasco |
| 0-1 | 36 | 1977 | Pan American Championship | B44 Sicilian |
69. P H Donoso Velasco vs G Garcia |
| ½-½ | 17 | 1977 | Pan American Championship | D30 Queen's Gambit Declined |
70. P H Donoso Velasco vs S Weeramantry |
| 1-0 | 43 | 1978 | Buenos Aires Olympiad | B08 Pirc, Classical |
71. Huebner vs P H Donoso Velasco |
| 1-0 | 43 | 1978 | Buenos Aires Olympiad | D45 Queen's Gambit Declined Semi-Slav |
72. P H Donoso Velasco vs Andersson |
| 0-1 | 51 | 1978 | Buenos Aires Olympiad | B42 Sicilian, Kan |
73. C Pritchett vs P H Donoso Velasco |
| ½-½ | 55 | 1978 | Buenos Aires Olympiad | C67 Ruy Lopez |
74. J Hebert vs P H Donoso Velasco |
| ½-½ | 74 | 1978 | Buenos Aires Olympiad | C45 Scotch Game |
75. P H Donoso Velasco vs A S Segal |
| ½-½ | 16 | 1978 | Buenos Aires Olympiad | C42 Petrov Defense |