| Game |
| Result | Moves |
Year |
Event/Locale | Opening |
| 26. Nezhmetdinov vs I Radulov |
 | 1-0 | 31 |
1967 |
Varna 4/413 | B31 Sicilian, Rossolimo Variation |
| 27. Platonov vs I Radulov |
| 1-0 | 34 |
1967 |
Sofia (Bulgaria) | D55 Queen's Gambit Declined |
| 28. I Radulov vs Bobotsov |
| 0-1 | 40 |
1967 |
BUL-ch | B89 Sicilian |
| 29. I Radulov vs A Kolarov |
| ½-½ | 25 |
1968 |
Varna | A89 Dutch, Leningrad, Main Variation with Nc6 |
| 30. Minev vs I Radulov |
| 1-0 | 52 |
1968 |
Varna | D55 Queen's Gambit Declined |
| 31. I Radulov vs Huebner |
| ½-½ | 44 |
1968 |
Lugano ol (Men) | B42 Sicilian, Kan |
| 32. I Radulov vs Bobotsov |
| 1-0 | 39 |
1968 |
Varna | B56 Sicilian |
| 33. L Day vs I Radulov |
 | 0-1 | 41 |
1968 |
Lugano | A12 English with b3 |
| 34. E Paoli vs I Radulov |
| 1-0 | 33 |
1968 |
Reggio Emilia | C11 French |
| 35. I Radulov vs A Hennings |
| ½-½ | 41 |
1968 |
Lugano ol (Men) | A12 English with b3 |
| 36. I Radulov vs G Sigurjonsson |
| ½-½ | 47 |
1969 |
Raach zt | C15 French, Winawer |
| 37. I Radulov vs Suetin |
| 0-1 | 39 |
1969 |
La Habana 8/353 | B48 Sicilian, Taimanov Variation |
| 38. Gligoric vs I Radulov |
| ½-½ | 34 |
1969 |
Capablanca mem | D35 Queen's Gambit Declined |
| 39. J Adamski vs I Radulov |
| ½-½ | 27 |
1969 |
Raach zt | E10 Queen's Pawn Game |
| 40. Hecht vs I Radulov |
| ½-½ | 46 |
1969 |
Raach zt | B31 Sicilian, Rossolimo Variation |
| 41. Portisch vs I Radulov |
 | 1-0 | 35 |
1969 |
Budapest | A10 English |
| 42. Bobotsov vs I Radulov |
| ½-½ | 42 |
1969 |
BUL-ch | D35 Queen's Gambit Declined |
| 43. I Radulov vs H Westerinen |
| 1-0 | 34 |
1969 |
Raach zt | C45 Scotch Game |
| 44. Korchnoi vs I Radulov |
| ½-½ | 41 |
1969 |
La Habana 8/492 | D54 Queen's Gambit Declined, Anti-Neo-Orthodox Variation |
| 45. I Radulov vs Smejkal |
| ½-½ | 22 |
1969 |
Raach zt | C56 Two Knights |
| 46. V Liberzon vs I Radulov |
| 1-0 | 23 |
1969 |
Debrecen | C78 Ruy Lopez |
| 47. I Radulov vs A Matanovic |
| ½-½ | 18 |
1969 |
Raach zt | B18 Caro-Kann, Classical |
| 48. I Radulov vs A Planinc |
| ½-½ | 32 |
1969 |
Cacak | C45 Scotch Game |
| 49. O'Kelly vs I Radulov |
| 0-1 | 35 |
1969 |
Habana (Cuba) | B61 Sicilian, Richter-Rauzer, Larsen Variation, 7.Qd2 |
| 50. Portisch vs I Radulov |
| ½-½ | 65 |
1969 |
Raach zt | D37 Queen's Gambit Declined |