| UTR Pro Blagoevgrad | 2025/03/09 08:00 | George Lazarov v Marcus Walters | 6-1,6-0 |
| UTR Pro Blagoevgrad | 2025/03/08 08:00 | George Lazarov v Marshall Tutu | 6-2,6-4 |
| UTR Pro Blagoevgrad | 2025/03/07 08:00 | Thomas Drayton v George Lazarov | 2-6,4-6 |
| UTR Pro Blagoevgrad | 2025/03/06 09:50 | Vardan Manukyan v George Lazarov | 4-6,1-6 |
| UTR Pro Blagoevgrad | 2025/03/04 08:00 | Nathan Blokhin v George Lazarov | 2-6,3-6 |
| UTR Pro Blagoevgrad | 2025/03/03 08:00 | George Lazarov v Mihnea Maftei | 6-2,7-5 |
| UTR Pro Blagoevgrad | 2025/02/08 09:40 | Petr Nesterov v George Lazarov | 6-4,6-7,6-2 |
| UTR Pro Blagoevgrad | 2025/02/06 08:00 | George Lazarov v Mateya Stanisavljevic | 6-2,6-3 |
| ITF M25 Caloundra | 2024/11/17 00:00 | Arjun Mehrotra v Stefan Kostic | 6-3,6-1 |
| ITF M25 Brisbane | 2024/11/10 01:00 | Finley Hall v Stefan Kostic | 6-3,7-6 |
| ITF M15 Kursumlijska Banja | 2024/08/28 10:20 | Stefan Kostic v Iannis Miletich | 4-6,2-6 |
| ITF M15 Pirot | 2024/08/21 10:10 | Stefan Kostic v Demetris Azoides | 0-6,2-6 |
| ITF M15 Kursumlijska Banja | 2024/08/14 07:00 | Stefan Latinov v Stefan Kostic | 6-1,7-6 |
| ITF M15 Kursumlijska Banja | 2024/08/08 09:00 | Stefan Kostic v Tommaso Compagnucci | 1-6,1-6 |
| ITF M15 Kursumlijska Banja | 2024/08/07 11:45 | Romeo Hadzimehmedovic v Stefan Kostic | 5-7,4-6 |
| ITF M15 Kursumlijska Banja | 2024/07/31 09:40 | Stefan Kostic v Franco Ribero | 2-6,2-6 |