| UTR Pro Tennis Series California | 2021/02/12 20:00 | Kyle Kang v Barrientos, Nicolas | 3-6,2-5 |
| UTR Pro Tennis Series California | 2021/05/29 16:30 | Colton Smith v Kyle Kang | 5-7,3-6 |
| UTR Pro Tennis Series California | 2021/05/28 16:30 | Humberto Lopez v Kyle Kang | 4-6,4-6 |
| UTR Pro Tennis Series California | 2021/05/26 16:30 | Thamma, Ivan v Kyle Kang | 6-7,4-5 |
| UTR Pro Tennis Series California | 2021/05/25 21:30 | Daniel Traxler v Kyle Kang | 1-6,2-6 |
| UTR Pro Tennis Series California | 2021/05/24 18:00 | Kyle Kang v Ravichander, Ishaan | 6-1,6-1 |
| UTR Pro Tennis Series California | 2021/05/23 15:00 | Kyle Kang v Joshua Sheehy | 7-5,6-3 |
| UTR Pro Tennis Series California | 2021/05/22 19:30 | Kyle Kang v Gomez, Lucas | 6-1,5-7,6-4 |
| UTR Pro Tennis Series California | 2021/05/21 16:30 | Isaiah Strode v Kyle Kang | 6-4,6-7,0-6 |
| UTR Pro Tennis Series California | 2021/05/29 15:00 | Ortlip, Joshua v Barrientos, Nicolas | 1-6,7-6,2-5 |
| UTR Pro Tennis Series California | 2021/05/28 16:30 | Hadigian, Eric v Barrientos, Nicolas | 3-6,2-6 |
| UTR Pro Tennis Series California | 2021/05/26 18:00 | Barrientos, Nicolas v Bailey, Aaron | 6-4,5-2 |
| UTR Pro Tennis Series California | 2021/05/25 18:30 | Barrientos, Nicolas v Kalman Boyd | 6-7,6-4,6-4 |
| UTR Pro Tennis Series California | 2021/05/24 16:30 | Rohan Murali v Barrientos, Nicolas | 0-6,1-6 |
| ITF - M25 Pensacola | 2021/05/19 16:30 | Adrian Andreev v Barrientos, Nicolas | 6-4,6-2 |
| ITF - M25 Pensacola | 2021/05/18 14:30 | Barrientos, Nicolas v Alexander Bernard | 4-6,6-1,10-4 |
| ITF - M25 Pensacola | 2021/05/17 15:30 | Barrientos, Nicolas v Tennyson Whiting | 6-2,6-3 |