| Game |
| Result | Moves |
Year |
Event/Locale | Opening |
| 1. U Jahr vs H H Sonntag |
| ½-½ | 63 |
1981 |
BL 8182 Markth'feld-Kettig | C44 King's Pawn Game |
| 2. W Bialas vs H H Sonntag |
| ½-½ | 66 |
1981 |
BL 8182 Kettig-Frankfurt | E69 King's Indian, Fianchetto, Classical Main line |
| 3. M Gerusel vs H H Sonntag |
| ½-½ | 65 |
1981 |
BL 8182 Kettig-Porz | D69 Queen's Gambit Declined, Orthodox Defense, Classical, 13.de |
| 4. G Jacoby vs H H Sonntag |
| ½-½ | 43 |
1982 |
BL 8182 HSK-Kettig | D35 Queen's Gambit Declined |
| 5. H H Sonntag vs M Dornieden |
| 1-0 | 50 |
1982 |
BL 8182 Delmenhorst-Kettig | A42 Modern Defense, Averbakh System |
| 6. H H Sonntag vs A Fehrig |
| 1-0 | 39 |
1982 |
BL 8182 Kettig-SKJE | B45 Sicilian, Taimanov |
| 7. H H Sonntag vs T Raupp |
| ½-½ | 19 |
1982 |
BL 8182 Zahringen-Kettig | B43 Sicilian, Kan, 5.Nc3 |
| 8. R Wittmann vs H H Sonntag |
| 0-1 | 54 |
1982 |
BL 8182 Kettig-Bochum | C95 Ruy Lopez, Closed, Breyer |
| 9. H H Sonntag vs V Ruehrig |
| 1-0 | 54 |
1982 |
BL 8182 Bamberg-Kettig | E82 King's Indian, Samisch, double Fianchetto Variation |
| 10. H H Sonntag vs J Dueball |
| 0-1 | 51 |
1982 |
BL 8182 Solingen-Kettig | E83 King's Indian, Samisch |
| 11. W Schmidt vs H H Sonntag |
| ½-½ | 27 |
1982 |
BRD-BL Kettig/Hamburg | C26 Vienna |
| 12. K Klundt vs H H Sonntag |
| 1-0 | 45 |
1982 |
BL 8182 Kettig-Bayern | C99 Ruy Lopez, Closed, Chigorin, 12...cd |
| 13. M Autenrieth vs H H Sonntag |
| 0-1 | 67 |
1984 |
BRD-BL Bochum/Erlangen | C26 Vienna |
| 14. Hertneck vs H H Sonntag |
| 1-0 | 42 |
1985 |
Bundesliga 8586 | D69 Queen's Gambit Declined, Orthodox Defense, Classical, 13.de |
| 15. H H Sonntag vs G Andruet |
| 0-1 | 37 |
1986 |
Bundesliga 8687 | B17 Caro-Kann, Steinitz Variation |
| 16. H Niedermaier vs H H Sonntag |
| 0-1 | 51 |
1986 |
BL 8687 Bochum-Bambe | C30 King's Gambit Declined |
| 17. H H Sonntag vs J Lechtynsky |
| 1-0 | 38 |
1986 |
Berlin op | E54 Nimzo-Indian, 4.e3, Gligoric System |
| 18. H H Sonntag vs Tringov |
| 1-0 | 43 |
1986 |
Berlin op | A75 Benoni, Classical with ...a6 and 10...Bg4 |
| 19. R Vogel vs H H Sonntag |
 | ½-½ | 10 |
1987 |
BL 8788 Zehlendorf-B | C32 King's Gambit Declined, Falkbeer Counter Gambit |
| 20. H H Sonntag vs Spassky |
| ½-½ | 48 |
1987 |
Ch FRG | C95 Ruy Lopez, Closed, Breyer |
| 21. Hertneck vs H H Sonntag |
| 1-0 | 50 |
1988 |
Berlin op | D68 Queen's Gambit Declined, Orthodox Defense, Classical |
| 22. Blatny vs H H Sonntag |
| 1-0 | 51 |
1989 |
Bad Woerishofen op | C84 Ruy Lopez, Closed |
| 23. F Marchand vs H H Sonntag |
| 0-1 | 27 |
1989 |
Chanac op | D59 Queen's Gambit Declined, Tartakower |
| 24. Nunn vs H H Sonntag |
| 0-1 | 61 |
1989 |
BL 8889 ;BL | C92 Ruy Lopez, Closed |
| 25. H H Sonntag vs Christiansen |
 | 0-1 | 16 |
1989 |
BL 8889 ;BL | A41 Queen's Pawn Game (with ...d6) |