| Game |
| Result | Moves |
Year |
Event/Locale | Opening |
| 1. H Westerinen vs C Zuidema |
| ½-½ | 66 |
1966 |
Orebro Stud olm fA | C97 Ruy Lopez, Closed, Chigorin |
| 2. H Westerinen vs Tringov |
| ½-½ | 46 |
1967 |
October Revolution 50 | C94 Ruy Lopez, Closed, Breyer Defense |
| 3. H Westerinen vs Keres |
| ½-½ | 60 |
1968 |
Helsinki FIN-EST (19.05.68) | C96 Ruy Lopez, Closed |
| 4. H Westerinen vs Smejkal |
 | 0-1 | 36 |
1969 |
Raach zt | C86 Ruy Lopez, Worrall Attack |
| 5. H Westerinen vs Portisch |
| 0-1 | 50 |
1969 |
Raach | C94 Ruy Lopez, Closed, Breyer Defense |
| 6. H Westerinen vs Timman |
| 1-0 | 25 |
1969 |
Vilnius | C90 Ruy Lopez, Closed |
| 7. H Westerinen vs Ivkov |
| 0-1 | 36 |
1970 |
Wijk aan Zee | C84 Ruy Lopez, Closed |
| 8. H Westerinen vs Gligoric |
 | 0-1 | 58 |
1971 |
FRG-ch int | C93 Ruy Lopez, Closed, Smyslov Defense |
| 9. H Westerinen vs Smejkal |
| 0-1 | 41 |
1971 |
Tallinn | C94 Ruy Lopez, Closed, Breyer Defense |
| 10. H Westerinen vs Teschner |
| ½-½ | 58 |
1971 |
FRG-ch int | C84 Ruy Lopez, Closed |
| 11. H Westerinen vs A Hennings |
| ½-½ | 37 |
1972 |
Helsinki | C94 Ruy Lopez, Closed, Breyer Defense |
| 12. H Westerinen vs Spassky |
| 0-1 | 37 |
1973 |
Tallinn (10) | C95 Ruy Lopez, Closed, Breyer |
| 13. H Westerinen vs E Gereben |
| 1-0 | 36 |
1973 |
Dortmund Schachtage | C97 Ruy Lopez, Closed, Chigorin |
| 14. H Westerinen vs Tseshkovsky |
| ½-½ | 51 |
1974 |
Sochi | C92 Ruy Lopez, Closed |
| 15. H Westerinen vs Antoshin |
| ½-½ | 40 |
1976 |
Reykjavik | C95 Ruy Lopez, Closed, Breyer |
| 16. H Westerinen vs Timman |
| 0-1 | 36 |
1976 |
02, Reykjavik | C95 Ruy Lopez, Closed, Breyer |
| 17. H Westerinen vs Razuvaev |
| ½-½ | 27 |
1976 |
EUCup final | C94 Ruy Lopez, Closed, Breyer Defense |
| 18. H Westerinen vs Angantysson |
| 0-1 | 45 |
1978 |
Lone Pine | C91 Ruy Lopez, Closed |
| 19. H Westerinen vs Reshevsky |
| ½-½ | 12 |
1979 |
Esjberg | C94 Ruy Lopez, Closed, Breyer Defense |
| 20. H Westerinen vs Szabo |
| 0-1 | 41 |
1979 |
Helsinki 27/320 | C99 Ruy Lopez, Closed, Chigorin, 12...cd |
| 21. H Westerinen vs E Torre |
| 1-0 | 35 |
1981 |
Bochum (Germany) | C99 Ruy Lopez, Closed, Chigorin, 12...cd |
| 22. H Westerinen vs Chiburdanidze |
| ½-½ | 30 |
1985 |
Havana-A | C84 Ruy Lopez, Closed |
| 23. H Westerinen vs G Timoshchenko |
| 0-1 | 42 |
1986 |
Helsinki | C88 Ruy Lopez |
| 24. H Westerinen vs Hebden |
| 0-1 | 39 |
1987 |
Gausdal YM | C84 Ruy Lopez, Closed |
| 25. H Westerinen vs E Forsaa |
| 1-0 | 30 |
2007 |
Arctic Chess Challenge | C88 Ruy Lopez |