46 games in the PremovedPrep archive. Games as White.
| White | Black | Result | ECO | Event | Date |
|---|---|---|---|---|---|
| Nielsen, Jon I Horni | Asllani, Muhamet | 1-0 | C78 | Olymp 2026 Open | 2026-09-27 |
| Nielsen, Jon I Horni | Roselli Mailhe, Bernardo | 1/2-1/2 | C03 | Olymp 2026 Open | 2026-09-23 |
| Nielsen, Jon I Horni | Gong, Daniel Hanwen | 1/2-1/2 | C07 | Olymp 2026 Open | 2026-09-20 |
| Nielsen, Jon I Horni | Donchenko, Alexander | 0-1 | B30 | Olymp 2026 Open | 2026-09-16 |
| Nielsen, Jon I Horni | Zerafa, Patrick | 1/2-1/2 | C90 | Round 9: Nielsen, Jon I Horni - Zerafa, Patrick | 2025-11-22 |
| Nielsen, Jon I Horni | Owen, Garth I | 1-0 | B52 | Round 8: Nielsen, Jon I Horni - Owen, Garth I | 2025-11-21 |
| Nielsen, Jon I Horni | Konstantinidis, Konstantinos | 1-0 | C71 | Round 6: Nielsen, Jon I Horni - Konstantinidis, Konstantinos | 2025-11-19 |
| Nielsen, Jon I Horni | Leardini, Mirko | 1-0 | B22 | Round 5: Nielsen, Jon I Horni - Leardini, Mirko | 2025-11-18 |
| Nielsen, Jon I Horni | Berend, Elvira | 0-1 | B40 | Round 2: Nielsen, Jon I Horni - Berend, Elvira | 2025-11-16 |
| Nahalka, Jan | Peglau, Charis | 0-1 | E00 | Tatrafest 2023 | 2023-10-01 |
| Nielsen Jon I Horni | Garban Mario | 1-0 | C78 | Open A | 2023-07-19 |
| Nahalka, Jan | Havetta, Slavomir | 1-0 | D11 | Piestany B | 2023-07-17 |
| Nielsen Jon I Horni | Sharon Rafael | 0-1 | B19 | Open A | 2023-07-17 |
| Nahalka, Jan | Silhankova, Simona | 1-0 | D09 | Piestany B | 2023-07-15 |
| Nielsen Jon I Horni | Balint Peter | 1-0 | B41 | Open A | 2023-07-15 |
| Nahalka, Jan | Volanek, Maros | 0-1 | D06 | Piestany B | 2023-07-14 |
| Nielsen Jon I Horni | Kulich Daniel | 1-0 | B19 | Open A | 2023-07-14 |
| Nielsen Jon I Horni | Kucharska Honorata | 0-1 | B28 | Open A | 2023-07-12 |
| Nahalka, Jan | Truskova, Stela | 1/2-1/2 | E00 | Piestany B | 2023-07-12 |
| Jon I Horni Nielsen | Konsta Kallunki | 0-1 | C65 | Nordic Youth Championship 2023 | 2023-02-19 |
| Jon I Horni Nielsen | Casper Liu | 1-0 | B15 | Nordic Youth Championship 2023 | 2023-02-18 |
| Jon I Horni Nielsen | Vignir Vatnar Stefansson | 1/2-1/2 | B30 | Nordic Youth Championship 2023 | 2023-02-17 |
| Nielsen, Jon I Horni | Elmi, Saad Abobaker | 1/2-1/2 | B51 | Nordic Youth Chess Championships 2022: Class B - U17 | 2022-08-28 |
| Nielsen, Jon I Horni | Meskenas, Paulius | 1-0 | C80 | Nordic Youth Chess Championships 2022: Class B - U17 | 2022-08-27 |
| Nielsen, Jon I Horni | Vainikka, Toni | 0-1 | C90 | Nordic Youth Chess Championships 2022: Class B - U17 | 2022-08-26 |