Stadium: Tammsaare 1 Round: 25 Ground: Hardcourt indoor
| ITF M15 Vejle | 2021/08/01 10:20 | Ergi Kirkin v August Holmgren | 7-6,6-4 |
| ITF M15 Vejle | 2021/07/31 07:50 | Ergi Kirkin v Zukas, Matias | 6-1,6-4 |
| ITF M15 Vejle | 2021/07/30 13:00 | Ergi Kirkin v Karl Friberg | 6-3,6-0 |
| ITF M15 Vejle | 2021/07/30 08:00 | Ergi Kirkin v Kotzen, Alexander | 6-2,6-3 |
| ITF M15 Vejle | 2021/07/28 10:25 | Ergi Kirkin v Del Federico, Andrea | 3-6,6-2,6-2 |
| Nur Sultan, Kazakhstan | 2021/07/20 09:10 | Ergi Kirkin v Ryan Peniston | 2-6,3-6 |
| Nur Sultan, Kazakhstan | 2021/07/19 06:10 | Ergi Kirkin v Benjamin Lock | 5-7,7-6,3-6 |
| Nur Sultan, Kazakhstan | 2021/07/12 04:00 | Ergi Kirkin v Oleksii Krutykh | 1-6,6-7 |
| UK Pro League | 2021/07/18 15:43 | Jack Gibbens v Weightman, Oscar | 3-6,6-4,0-0 |
| UK Pro League | 2021/07/18 14:30 | Weightman, Oscar v Jack Gibbens | 6-3,4-6,11-13 |
| UK Pro League | 2021/07/16 10:00 | Weightman, Oscar v Liam Hignett | 7-6,6-4 |
| UK Pro League | 2021/07/15 11:30 | Maxted, Lui v Weightman, Oscar | 6-3,6-3 |
| UK Pro League | 2021/07/14 10:00 | Weightman, Oscar v Hands, Tom | 6-3,6-3 |
| UK Pro League | 2021/07/12 10:00 | Cash, Julian v Weightman, Oscar | 6-7,6-4,10-6 |
| ITF - M15 Monastir | 2021/06/24 10:10 | Weightman, Oscar v Duckhee Lee | 3-6,7-6,3-6 |
| ITF - M15 Monastir | 2021/06/23 13:30 | Weightman, Oscar v Kelsey Stevenson | 1-6,7-5,7-5 |