Stadium: Indoor Ct. 5 Round: 27 Ground: Hardcourt outdoor
| ITF M15 Champaign | 2021/06/24 15:00 | Genaro Alberto Olivieri v Gabriel Diallo | 3-6,6-7 |
| ITF M15 Champaign | 2021/06/23 19:05 | Benjamin Sigouin v Gabriel Diallo | 3-6,2-6 |
| ITF M15 Champaign | 2021/06/22 15:00 | Peter Bertran v Gabriel Diallo | 1-6,0-6 |
| ITF M15 Champaign | 2021/06/21 15:00 | Gabriel Diallo v Nicaise Muamba | 7-5,6-3 |
| ITF M25 Wichita | 2021/06/09 19:20 | Patrick Kypson v Gabriel Diallo | 6-4,6-4 |
| ITF M25 Wichita | 2021/06/08 16:45 | Mark Mandlik v Gabriel Diallo | 2-6,7-6,9-11 |
| ITF M25 Wichita | 2021/06/07 15:00 | Gabriel Diallo v Eric Hadigian | 6-2,7-6 |
| Challenger Calgary | 2020/02/25 21:30 | Gage Brymer v Gabriel Diallo | 6-2,7-6 |
| ITF M15 Champaign | 2021/06/24 17:25 | Khololwam Montsi v Ezekiel Clark | 4-6,6-4,6-1 |
| ITF M15 Champaign | 2021/06/23 18:45 | Khololwam Montsi v Ben Shelton | 6-4,4-6,7-5 |
| ITF M15 Jerusalem | 2021/05/11 06:30 | Khololwam Montsi v Julian Cash | 5-7,6-4,5-7 |
| ITF M15 Ramat Hasharon | 2021/05/05 07:00 | Khololwam Montsi v Ben Patael | 4-6,1-6 |
| ITF M15 Sharm El Sheikh | 2021/03/10 07:30 | Edoardo Eremin v Khololwam Montsi | 6-3,4-6,6-4 |
| ITF M15 Sharm El Sheikh | 2021/03/03 13:00 | Jakub Paul v Khololwam Montsi | 6-1,7-6 |
| Challenger Potchefstroom | 2021/02/18 08:00 | Adrian Menendez-Maceiras v Khololwam Montsi | 6-3,6-0 |
| Challenger Potchefstroom | 2021/02/16 08:00 | Khololwam Montsi v Brayden Schnur | 6-4,6-1 |