Stadium: Court 6 Round: 19 Ground: Hardcourt outdoor
| Challenger - Tenerife | 2024/01/14 13:10 | August Holmgren v Ivan Marrero Curbelo | 6-4,6-2 |
| Challenger - Oeiras | 2024/01/10 10:30 | Alejandro Moro Canas v August Holmgren | 6-3,7-5 |
| Challenger Yokkaichi | 2023/12/01 05:05 | August Holmgren v Coleman Wong | 6-4,5-7,4-6 |
| Challenger Yokkaichi | 2023/11/29 03:00 | Zdenek Kolar v August Holmgren | 4-6,2-6 |
| Challenger Yokkaichi | 2023/11/28 03:20 | Yusuke Takahashi v August Holmgren | 3-6,3-6 |
| Challenger Yokkaichi | 2023/11/27 01:00 | August Holmgren v Kai Wehnelt | 6-2,6-4 |
| Challenger - Yokohama | 2023/11/21 02:45 | August Holmgren v Giovanni Fonio | 4-6,1-6 |
| Challenger - Yokohama | 2023/11/20 01:00 | August Holmgren v Naoki Tajima | 3-6,7-5,6-3 |
| Challenger - Tenerife | 2024/01/14 15:00 | Alexey Vatutin v Guy Den Ouden | 0-6,3-6 |
| Challenger - Oeiras - Kwal. | 2024/01/07 12:20 | Alexis Gautier v Guy Den Ouden | 6-4,6-7,6-3 |
| ITF - M15 Monastir | 2023/12/10 08:45 | Jakub Paul v Guy Den Ouden | 3-6,2-6 |
| ITF - M15 Monastir | 2023/12/09 11:00 | Paul Jubb v Guy Den Ouden | 4-6,4-6 |
| ITF - M15 Monastir | 2023/12/08 09:00 | Mark Wallner v Guy Den Ouden | 4-6,1-6 |
| ITF - M15 Monastir | 2023/12/07 11:00 | Sebastian Sorger v Guy Den Ouden | 6-2,1-6,0-6 |
| ITF - M15 Monastir | 2023/12/06 13:40 | Attila Boros v Guy Den Ouden | 1-6,7-5,2-6 |
| ITF - M25 Monastir | 2023/12/02 09:00 | Bogdan Bobrov v Guy Den Ouden | 6-3,7-6 |