Stadium: Stadium 1 Round: 14 Ground: Hardcourt outdoor
| ATP Newport | 2021/07/11 21:40 | Darian King v Ramkumar Ramanathan | 3-6,4-6 |
| Challenger Orlando | 2021/06/07 20:15 | Jenson Brooksby v Darian King | 7-6,6-3 |
| Challenger Little Rock | 2021/06/02 21:00 | Darian King v Mitchell Krueger | 3-6,2-6 |
| Challenger Little Rock | 2021/05/31 19:35 | Darian King v Thiago Agustin Tirante | 6-4,6-4 |
| ATP Belgrad | 2021/05/22 14:25 | Christopher O'Connell v Darian King | 6-1,6-3 |
| Challenger Orlando | 2021/04/12 15:30 | Jesper De Jong v Darian King | 6-0,6-3 |
| Challenger Cleveland | 2021/03/17 15:15 | Christopher Eubanks v Darian King | 6-1,6-2 |
| Challenger Cleveland | 2021/03/16 14:00 | Darian King v Mitchell Krueger | 6-3,5-7,7-5 |
| ITF - Champaign M15 | 2021/06/27 15:00 | Jason Kubler v Gabriel Diallo | 6-2,6-1 |
| ITF - Champaign M15 | 2021/06/26 15:00 | Gabriel Diallo v Kyle Seelig | 6-4,6-3 |
| ITF - Champaign M15 | 2021/06/25 17:00 | Gabriel Diallo v Khololwam Montsi | 7-5,6-3 |
| ITF - Champaign M15 | 2021/06/24 15:00 | Genaro Alberto Olivieri v Gabriel Diallo | 3-6,6-7 |
| ITF - Champaign M15 | 2021/06/23 19:05 | Benjamin Sigouin v Gabriel Diallo | 3-6,2-6 |
| ITF - Champaign M15 | 2021/06/22 15:00 | Peter Bertran v Gabriel Diallo | 1-6,0-6 |
| ITF - Champaign M15 | 2021/06/21 15:00 | Gabriel Diallo v Nicaise Muamba | 7-5,6-3 |
| ITF - Wichita M25 | 2021/06/09 19:20 | Patrick Kypson v Gabriel Diallo | 6-4,6-4 |