| Game |
| Result | Moves |
Year | Event/Locale | Opening |
| 176. M Diesen vs Westerinen |
| ½-½ | 12 | 1977 | New York GHI | E98 King's Indian, Orthodox, Taimanov, 9.Ne1 |
| 177. A Lein vs M Diesen |
| ½-½ | 10 | 1977 | New York GHI | A49 King's Indian, Fianchetto without c4 |
| 178. M Diesen vs R Henley |
| ½-½ | 13 | 1977 | New York GHI | B08 Pirc, Classical |
| 179. A Beliavsky vs M Diesen |
| 1-0 | 41 | 1978 | Alicante | D25 Queen's Gambit Accepted |
| 180. M Diesen vs A Medina Garcia |
| 1-0 | 40 | 1978 | Alicante | C76 Ruy Lopez, Modern Steinitz Defense, Fianchetto Variation |
| 181. A Fernandez Fernandez vs M Diesen |
| ½-½ | 27 | 1978 | Alicante | B90 Sicilian, Najdorf |
| 182. M Diesen vs J L Vilela |
| ½-½ | 41 | 1978 | Alicante | E15 Queen's Indian |
| 183. F Sanz Alonso vs M Diesen |
| ½-½ | 36 | 1978 | Alicante | C10 French |
| 184. M Diesen vs E Ermenkov |
| ½-½ | 21 | 1978 | Alicante | D85 Grunfeld |
| 185. M Rohde vs M Diesen |
| ½-½ | 22 | 1978 | Alicante | B89 Sicilian |
| 186. M Diesen vs A Martin Gonzalez |
| 1-0 | 42 | 1978 | Alicante | B76 Sicilian, Dragon, Yugoslav Attack |
| 187. O Rodriguez Vargas vs M Diesen |
| 0-1 | 28 | 1978 | Alicante | D31 Queen's Gambit Declined |
| 188. M Diesen vs J Hernando Pertierra |
| ½-½ | 39 | 1978 | Alicante | B01 Scandinavian |
| 189. M Diesen vs J Ochoa |
| ½-½ | 22 | 1978 | Alicante | B45 Sicilian, Taimanov |
| 190. M Diesen vs M Damjanovic |
| ½-½ | 14 | 1978 | Alicante | E11 Bogo-Indian Defense |
| 191. M J Verdu vs M Diesen |
| 0-1 | 32 | 1978 | Alicante | A34 English, Symmetrical |
| 192. M Diesen vs H D MacPherson |
| 1-0 | 20 | 1978 | Aaronson Masters | C00 French Defense |
| 193. A H Perkins vs M Diesen |
| 0-1 | 37 | 1978 | Aaronson Masters | D47 Queen's Gambit Declined Semi-Slav |
| 194. C Crouch vs M Diesen |
| ½-½ | 17 | 1978 | Aaronson Masters | B13 Caro-Kann, Exchange |
| 195. M Diesen vs P Littlewood |
| 1-0 | 66 | 1978 | Aaronson Masters | A28 English |
| 196. M Diesen vs A P Law |
| ½-½ | 12 | 1978 | Aaronson Masters | B80 Sicilian, Scheveningen |
| 197. R Bellin vs M Diesen |
| ½-½ | 12 | 1978 | Aaronson Masters | D00 Queen's Pawn Game |
| 198. M J Franklin vs M Diesen |
| ½-½ | 15 | 1978 | Aaronson Masters | D05 Queen's Pawn Game |
| 199. M Diesen vs W Hartston |
| ½-½ | 8 | 1978 | Aaronson Masters | D53 Queen's Gambit Declined |
| 200. A Haik vs M Diesen |
| ½-½ | 50 | 1978 | Aaronson Masters | E34 Nimzo-Indian, Classical, Noa Variation |
Kibitzing
