Stadium: Court 6 Round: 25 Ground: Clay
| ITF M15 Alkmaar | 2024/06/24 08:00 | Lodewijk Weststrate v Stian Klaassen | 6-3,2-6,10-4 |
| ITF M15 San Diego | 2024/06/13 17:00 | Patrick Maloney v Stian Klaassen | 6-2,5-7,6-0 |
| ITF M15 San Diego | 2024/06/12 20:25 | Stian Klaassen v James Tracy | 6-2,1-6,6-4 |
| ITF M15 San Diego | 2024/06/11 17:00 | Joshua Charlton v Stian Klaassen | 3-6,3-6 |
| ITF M15 San Diego | 2024/06/04 16:00 | Stian Klaassen v Christopher Bulus | 4-6,2-6 |
| ITF M15 San Diego | 2024/06/03 16:00 | Benjamin Thomas George v Stian Klaassen | 0-6,0-6 |
| ITF M15 San Diego | 2024/05/27 16:00 | Robin Catry v Stian Klaassen | 6-3,6-4 |
| ITF M15 Eindhoven | 2023/08/02 11:00 | Elmer Moller v Stian Klaassen | 6-0,6-2 |
| ITF M15 Saarlouis | 2024/06/22 11:00 | Michael Vrbensky v Niels Visker | 1-6,6-1,6-4 |
| ITF M15 Saarlouis | 2024/06/21 10:30 | Bogdan Bobrov v Niels Visker | 2-6,7-6,2-6 |
| ITF M15 Saarlouis | 2024/06/20 11:30 | Giuseppe Tresca v Niels Visker | 1-6,2-6 |
| ITF M15 Saarlouis | 2024/06/19 08:00 | Sebastian Prechtel v Niels Visker | 4-6,2-6 |
| ITF M15 Bucharest | 2024/05/14 11:25 | Eric Vanshelboim v Niels Visker | 6-1,3-6,6-3 |
| ITF M15 Bucharest | 2024/05/10 09:45 | Niels Lootsma v Niels Visker | 6-3,7-6 |
| ITF M15 Bucharest | 2024/05/09 08:40 | Niels Visker v Yurii Dzhavakian | 6-3,6-1 |
| ITF M15 Bucharest | 2024/05/07 09:30 | Niels Visker v Alejandro M B Nourescu | 6-4,7-5 |