Stadium: Court 5 Round: 14 Ground: Hardcourt indoor
| ITF M15 Naples | 2021/10/10 14:00 | Cornut-Chauvinc, Antoine v Harrison, Ryan | 3-6,5-7 |
| ITF M15 Naples | 2021/10/09 14:00 | Damien Wenger v Harrison, Ryan | 3-6,5-7 |
| ITF M15 Naples | 2021/10/08 14:30 | Peter Bertran v Harrison, Ryan | 3-6,1-6 |
| ITF M15 Naples | 2021/10/07 15:35 | Juncheng Shang v Harrison, Ryan | 3-6,2-6 |
| ITF M15 Naples | 2021/10/06 19:25 | Louroi Martinez v Harrison, Ryan | 6-7,3-6 |
| Challenger - Barletta | 2021/08/23 11:00 | Luca Potenza v Harrison, Ryan | 3-6,6-3,2-6 |
| Challenger - Barletta | 2021/08/22 12:50 | Harrison, Ryan v Alexis Galarneau | 6-4,6-3 |
| ITF M25 Ueberlingen | 2021/08/20 11:30 | Harrison, Ryan v Esteve Lobato, Eduard | 1-6,4-6 |
| Sydney, Australia | 2022/01/09 00:00 | Daniel Altmaier v Pervolarakis, Michail | 6-4,6-1 |
| ATP Cup, Playoffs | 2022/01/05 06:30 | Pervolarakis, Michail v Aleksandre Metreveli | 6-3,6-2 |
| ATP Cup, Playoffs | 2022/01/03 06:30 | Pervolarakis, Michail v Delbonis, Federico | 6-7,1-6 |
| ATP Cup, Playoffs | 2022/01/01 06:30 | Pervolarakis, Michail v Kamil Majchrzak | 1-6,4-6 |
| Forli 6, Italy | 2021/12/10 15:30 | Arnaboldi, Andrea v Pervolarakis, Michail | 6-4,6-3 |
| Forli 6, Italy | 2021/12/09 17:35 | Pervolarakis, Michail v Baldi, Filippo | 6-4,6-4 |
| Forli 6, Italy | 2021/12/07 11:40 | Pervolarakis, Michail v Luca Potenza | 6-3,6-4 |
| Challenger Manama | 2021/11/22 09:55 | Vladyslav Orlov v Pervolarakis, Michail | 1-6,6-4,6-0 |