Stadium: Court 07 Round: 62 Ground: Clay
| ITF M15 Warmbad-Villach | 2021/08/15 07:00 | Erwin Troebinger v Martin Zeljenka | 5-7,1-6 |
| ITF M25 Pitesti | 2021/08/02 10:00 | Martin Zeljenka v Vladislav Melnic | 3-6,6-7 |
| ITF M25 Pitesti | 2021/08/01 13:30 | Martin Zeljenka v Samuil Konov | 6-4,6-4 |
| ITF M15 Novi Sad | 2021/07/25 07:00 | Martin Zeljenka v Danilo Raicevic | 4-6,4-6 |
| ITF M25 Kottingbrunn | 2021/07/19 12:25 | Peter Goldsteiner v Martin Zeljenka | 6-4,7-6 |
| ITF M25 Kottingbrunn | 2021/07/18 07:30 | Martin Zeljenka v Rafael Kis Balazs | 2-6,6-4,10-2 |
| ITF M25 Belgrade | 2021/06/29 07:00 | Bogdan Pavel v Martin Zeljenka | 6-1,6-3 |
| ITF M25 Belgrade | 2021/06/28 10:00 | Martin Zeljenka v Matvey Minin | 7-5,6-3 |
| ITF M15 Warmbad-Villach | 2021/08/15 07:00 | Jonas Greif v Gabriel Decamps | 0-6,2-6 |
| ITF M15 Frederiksberg | 2021/08/04 07:50 | Benjamin Hannestad v Gabriel Decamps | 6-4,6-2 |
| ITF M15 Frederiksberg | 2021/08/02 12:35 | Gabriel Decamps v Benedikt Emesz | 6-1,6-4 |
| ITF M15 Frederiksberg | 2021/08/01 10:00 | Gabriel Decamps v Simon Friis Soendergaard | 6-4,6-2 |
| ITF M15 Vejle | 2021/07/28 12:45 | Gabriel Decamps v Mick Veldheer | 3-6,1-6 |
| ITF M15 Vejle | 2021/07/26 14:00 | Gabriel Decamps v Benjamin Hannestad | 0-6,7-6,10-6 |
| ITF M15 Vejle | 2021/07/25 09:00 | Martins Rocens v Gabriel Decamps | 1-6,2-6 |
| ITF M25 Uriage | 2021/07/15 11:00 | Giovanni Mpetshi Perricard v Gabriel Decamps | 6-3,6-3 |