Stadium: Court 17 Round: 14 Ground: Grass
| ITF W25 Madrid | 2021/06/11 07:15 | Robin Anderson v Kostova, Elitsa | 7-6,6-2 |
| ITF W25 Madrid | 2021/06/10 10:35 | Yvonne Cavalle-Reimers v Kostova, Elitsa | 6-3,2-6,5-7 |
| ITF W25 Madrid | 2021/06/09 09:05 | Poznikhirenko, Ganna v Kostova, Elitsa | 3-6,3-6 |
| Open de France - Femmes | 2021/05/26 08:30 | Kostova, Elitsa v Ekaterine Gorgodze | 6-7,3-6 |
| Open de France - Femmes | 2021/05/24 08:30 | Djoubri, Salma v Kostova, Elitsa | 3-6,2-6 |
| UTR Pro Tennis Series Pazardzhik Women | 2021/05/16 08:00 | Kostova, Elitsa v Darja Semenistaja | 6-1,6-3 |
| UTR Pro Tennis Series Pazardzhik Women | 2021/05/15 07:30 | Kostova, Elitsa v Julia Terziyska | 6-4,5-1 |
| UTR Pro Tennis Series Pazardzhik Women | 2021/05/14 10:30 | Shalamanova, Daria v Kostova, Elitsa | 2-6,3-5 |
| ITF W60 Stare Splavy | 2021/06/16 13:05 | Destanee Aiava v Cadantu, Alexandra | 3-6,3-6 |
| ITF W25 Madrid | 2021/06/10 07:15 | Destanee Aiava v Amandine Hesse | 1-6,3-6 |
| ITF W25 Madrid | 2021/06/09 11:30 | Destanee Aiava v Cristina Dinu | 6-4,6-1 |
| ITF W25 Otocec | 2021/06/01 12:45 | Rebecca Sramkova v Destanee Aiava | 6-2,6-3 |
| ITF W25 Otocec | 2021/05/26 11:40 | Rosca, Ioana Loredana v Destanee Aiava | 7-6,1-6,6-3 |
| ITF W60 Saint-Gaudens | 2021/05/13 11:50 | Destanee Aiava v Nara, Kurumi | 6-4,3-6,6-7 |
| ITF W60 Saint-Gaudens | 2021/05/11 16:40 | Destanee Aiava v Guttierez Carrasco, Maria | 6-3,6-2 |
| ITF W25 Prague | 2021/05/04 11:55 | Rebecca Sramkova v Destanee Aiava | 6-1,6-4 |