Stadium: Center Court Round: 25 Ground: Clay
| ITF - W60 Versmold | 2021/07/28 11:00 | Richel Hogenkamp v Joelle Lilly Sophie Steur | 6-4,7-6 |
| ITF - W15 Alkmaar | 2021/06/21 15:00 | Anna Ozerova v Joelle Lilly Sophie Steur | 6-7,3-6 |
| ITF - W15 Alkmaar | 2021/06/20 09:30 | Joelle Lilly Sophie Steur v Larisa Bekmetova | 6-0,6-1 |
| German Championship - Feminin | 2020/12/07 09:30 | Joelle Lilly Sophie Steur v Selina Dal | 3-6,7-5,0-5 |
| DTB German Pro Series - Feminin | 2020/07/03 11:15 | Lisa Ponomar v Joelle Lilly Sophie Steur | 6-1,7-6 |
| DTB German Pro Series - Feminin | 2020/07/02 11:45 | Katharina Hering v Joelle Lilly Sophie Steur | 7-6,7-6 |
| DTB German Pro Series - Feminin | 2020/07/01 11:55 | Lisa Ponomar v Joelle Lilly Sophie Steur | 5-7,3-6 |
| DTB German Pro Series - Feminin | 2020/06/30 08:00 | Carmen Schultheiss v Joelle Lilly Sophie Steur | 4-6,6-4,3-6 |
| ITF - W25 Koksijde | 2021/08/08 13:00 | Berta Bonardi v Natalia Siedliska | 7-6,6-7,10-6 |
| ITF - W15 Knokke | 2021/07/31 12:05 | Natalia Siedliska v Selena Janicijevic | 6-4,5-7,2-6 |
| ITF - W15 Knokke | 2021/07/30 10:10 | Michaela Bayerlova v Natalia Siedliska | 6-3,2-6,1-6 |
| ITF - W15 Knokke | 2021/07/29 14:00 | Bojana Marinkovic v Natalia Siedliska | 2-6,4-6 |
| ITF - W15 Knokke | 2021/07/27 12:05 | Noa Liauw A Fong v Natalia Siedliska | 4-6,3-6 |
| ITF - W15 L'Aquila | 2021/06/23 08:30 | Caijsa W Hennemann v Natalia Siedliska | 2-6,4-6 |
| ITF - W15 Antalya | 2021/06/08 08:40 | Natalia Siedliska v Anet A Koskel | 6-2,6-0 |
| ITF - W15 Antalya | 2021/06/04 07:25 | Manon Arcangioli v Natalia Siedliska | 7-6,2-6,6-2 |