| Challenger Banja Luka | 2021/09/07 11:30 | Matija Pecotic v Marko Tepavac | 4-6,6-3,7-6 |
| Challenger Prague | 2021/08/25 08:00 | Matija Pecotic v Facundo Diaz Acosta | 3-6,6-7 |
| Challenger Prague | 2021/08/23 12:15 | Evgeny Tyurnev v Matija Pecotic | 6-7,2-6 |
| Challenger Verona | 2021/08/17 19:00 | Holger Rune v Matija Pecotic | 6-2,7-6 |
| Challenger Verona | 2021/08/16 09:00 | Flavio Cobolli v Matija Pecotic | 3-6,4-6 |
| Challenger Verona | 2021/08/15 13:35 | Nicolo Pozzani v Matija Pecotic | 2-6,4-6 |
| Challenger Prague | 2021/08/08 12:00 | Facundo Diaz Acosta v Matija Pecotic | 7-6,6-1 |
| ATP Umag | 2021/07/19 14:30 | Daniel Altmaier v Matija Pecotic | 3-6,6-4,6-3 |