Stadium: Court 6 Round: 54 Ground: Clay
| ITF M25 Alkmaar | 2021/06/20 10:30 | Garanganga, Takanyi v Dermiens, Guillaume | 3-6,1-6 |
| ITF - M15 Antalya | 2021/06/08 07:00 | Franco Roncadelli v Dermiens, Guillaume | 6-2,6-0 |
| ITF - M15 Antalya | 2021/06/07 09:35 | Credit Chaiyarin v Dermiens, Guillaume | 0-6,4-6 |
| ITF - M15 Antalya | 2021/05/31 08:30 | Nicolas Parizzia v Dermiens, Guillaume | 6-3,1-6,10-5 |
| ITF - M15 Monastir | 2021/04/11 11:00 | Dermiens, Guillaume v Arthur Bouquier | 6-4,5-7,10-12 |
| ITF - M15 Monastir | 2021/04/05 09:00 | Hazem Naw v Dermiens, Guillaume | 6-2,6-2 |
| ITF - M15 Monastir | 2021/04/04 10:30 | Dermiens, Guillaume v Samuel Puskar | 6-2,6-3 |
| ITF - M15 Monastir | 2021/03/08 12:30 | Dermiens, Guillaume v de La Bassetiere, Constant | 3-6,2-6 |
| ITF M25 Alkmaar | 2021/06/20 12:30 | Lodewijk Weststrate v Eisinga, Zachary | 2-6,1-6 |
| ITF M15 Cairo | 2021/05/04 08:00 | Eisinga, Zachary v Dimitrov, Martin | 1-6,6-7 |
| ITF M15 Cairo | 2021/05/03 08:00 | Eisinga, Zachary v Ali Alshati | 3-6,6-0,10-8 |
| ITF M15 Cairo | 2021/04/28 10:00 | Eisinga, Zachary v Shintaro Mochizuki | 4-6,2-6 |
| ITF M15 Cairo | 2021/04/19 10:30 | Eisinga, Zachary v Fares Zakaria | 2-6,6-3,3-10 |
| ITF M15 Cairo | 2021/04/18 07:00 | Eisinga, Zachary v Magnusson, Anton | 6-2,4-6,10-2 |
| ITF M15 Alkmaar | 2020/08/24 08:30 | Raphael Collignon v Eisinga, Zachary | 6-4,6-3 |
| ITF M15 Alkmaar | 2020/08/23 08:30 | Cheraag Bajwa v Eisinga, Zachary | 1-6,2-6 |