| Game |
| Result | Moves |
Year | Event/Locale | Opening |
| 1. F Middendorf vs H Bastian |
| 1-0 | 45 | 1969 | FRG-ch U20 | A49 King's Indian, Fianchetto without c4 |
| 2. H Mossong vs F Middendorf |
| ½-½ | 42 | 1969 | Niemeyer Juniors Preliminary | B15 Caro-Kann |
| 3. F Middendorf vs A Urzica |
| ½-½ | 22 | 1969 | Niemeyer Juniors Preliminary | A09 Reti Opening |
| 4. C Pritchett vs F Middendorf |
| 1-0 | 30 | 1969 | Niemeyer Juniors Preliminary | A01 Nimzovich-Larsen Attack |
| 5. F Middendorf vs A Loeffler |
| 1-0 | 30 | 1969 | Niemeyer Juniors Preliminary | D45 Queen's Gambit Declined Semi-Slav |
| 6. B Jacobsen vs F Middendorf |
| 1-0 | 50 | 1969 | Niemeyer Juniors Preliminary | A03 Bird's Opening |
| 7. F Middendorf vs P G Henry |
| 1-0 | 47 | 1969 | Niemeyer Juniors Preliminary | E12 Queen's Indian |
| 8. T Ristoja vs F Middendorf |
| 1-0 | 56 | 1969 | Niemeyer Juniors Preliminary | B51 Sicilian, Canal-Sokolsky (Rossolimo) Attack |
| 9. E J Holt vs F Middendorf |
| ½-½ | 23 | 1970 | Zuerich | B93 Sicilian, Najdorf, 6.f4 |
| 10. Fischer vs F Middendorf |
 | 1-0 | 23 | 1970 | Fischer Simul, 20b Muenster | B87 Sicilian, Fischer-Sozin with ...a6 and ...b5 |
| 11. M Eisinger vs F Middendorf |
| ½-½ | 25 | 1972 | West German Championship | B94 Sicilian, Najdorf |
| 12. W Berner vs F Middendorf |
| ½-½ | 41 | 1972 | West German Championship | A04 Reti Opening |
| 13. F Gragger vs F Middendorf |
| 0-1 | 35 | 1972 | West German Championship | B94 Sicilian, Najdorf |
| 14. S Heil vs F Middendorf |
| 0-1 | 27 | 1972 | West German Championship | B90 Sicilian, Najdorf |
| 15. M Heilemann vs F Middendorf |
| ½-½ | 40 | 1972 | West German Championship | A43 Old Benoni |
| 16. F Middendorf vs M Gerusel |
| 0-1 | 36 | 1972 | West German Championship | A49 King's Indian, Fianchetto without c4 |
| 17. F Middendorf vs H Kestler |
| 1-0 | 26 | 1972 | West German Championship | A16 English |
| 18. F Middendorf vs U Kunsztowicz |
| ½-½ | 42 | 1972 | West German Championship | A05 Reti Opening |
| 19. F Middendorf vs G Nippgen |
| 1-0 | 41 | 1972 | West German Championship | D78 Neo-Grunfeld, 6.O-O c6 |
| 20. F Middendorf vs W Reichenbach |
| 1-0 | 37 | 1972 | West German Championship | A15 English |
| 21. F Middendorf vs R Scheipl |
| 0-1 | 38 | 1972 | West German Championship | A17 English |
| 22. F Middendorf vs A Suess |
| ½-½ | 13 | 1972 | West German Championship | D78 Neo-Grunfeld, 6.O-O c6 |
| 23. F Middendorf vs D Weise |
| 0-1 | 21 | 1972 | West German Championship | A15 English |
| 24. T Peine vs F Middendorf |
| 0-1 | 49 | 1972 | West German Championship | B90 Sicilian, Najdorf |
| 25. K Podzielny vs F Middendorf |
| ½-½ | 30 | 1972 | West German Championship | B96 Sicilian, Najdorf |
Kibitzing
