Stadium: Court 2 Round: 25 Ground: Hardcourt indoor
| ITF M15 Selva Gardena | 2021/10/25 12:40 | Michael Gloeckler v Alessio Tramontin | 7-5,3-6,10-7 |
| ITF M15 Selva Gardena | 2021/10/24 16:35 | Michael Gloeckler v Giovanni Agostinetto | 7-6,7-6 |
| ITF M15 Sozopol | 2021/10/11 10:00 | Nikolay Nedelchev v Michael Gloeckler | 6-0,6-3 |
| ITF M15 Sozopol | 2021/10/10 12:00 | Maxim Khorozov v Michael Gloeckler | 7-6,2-6,5-10 |
| ITF M15 Sozopol | 2021/10/05 06:30 | Nikolay Nedelchev v Michael Gloeckler | 6-0,6-3 |
| ITF M15 Sozopol | 2021/10/04 07:00 | Samuil Konov v Michael Gloeckler | 3-6,4-6 |
| ITF M25 Pardubice | 2021/09/20 08:00 | Noah Schlagenhauf v Michael Gloeckler | 6-3,6-2 |
| UTR Pro Tennis Series Ricany | 2021/09/18 07:30 | Lawrence Bataljin v Michael Gloeckler | 6-4,5-2 |
| ITF M15 Sharm El Sheikh | 2021/10/20 12:25 | Marat Deviatiarov v Andrea Guerrieri | 6-4,6-0 |
| ITF M15 Sharm El Sheikh | 2021/10/13 08:00 | Michal Mikula v Andrea Guerrieri | 7-6,7-6 |
| ITF M15 Bad Waltersdorf | 2021/09/01 08:00 | Andrea Guerrieri v Giorgio Tabacco | 4-6,4-6 |
| ITF M15 Warmbad-Villach | 2021/08/18 08:00 | Peter Heller v Andrea Guerrieri | 6-1,6-1 |
| ITF M15 Gdynia | 2021/08/09 08:00 | Andrea Guerrieri v Juliusz Bienkiewicz | 6-2,2-6,7-10 |
| ITF M15 Parnu | 2021/08/05 09:55 | Yan Sabanin v Andrea Guerrieri | 6-2,6-3 |
| ITF M15 Parnu | 2021/08/04 16:00 | Andrea Guerrieri v Johannes Seeman | 2-6,7-6,6-4 |
| ITF M15 Bergamo | 2021/06/21 12:00 | Andrea Guerrieri v Francesco Vilardo | 6-7,6-2,10-12 |