USA: Houston - Singles - Main |
| 1/16-finals | Nguyen D. | Jung J. | 0:2 (3:6, 2:6) | details | 13.11.2019 |
| 1/32-finals | Sarkar S. | Nguyen D. | 0:2 (1:6, 0:6) | details | 12.11.2019 |
USA: Waco - Singles - Main |
| 1/16-finals | Nguyen D. | Chappell N. | CAN. | details | 16.10.2019 |
USA: Columbus 3 - Singles - Main |
| 1/32-finals | Nguyen D. | Petit G. | 1:2 (63:7, 6:3, 4:6) | details | 16.09.2019 |
USA: Cary - Singles - Main |
| 1/8-finals | Nguyen D. | Aragone J. | 0:2 (3:6, 2:6) | details | 12.09.2019 |
| 1/16-finals | Krueger M. | Nguyen D. | 1:2 (3:6, 6:3, 3:6) | details | 11.09.2019 |
| 1/32-finals | Nguyen D. | Sigouin B. | 2:0 (6:1, 6:3) | details | 09.09.2019 |
USA: Winston-Salem - Singles - Qualification |
| Final | Sarmiento R. | Nguyen D. | 2:0 (6:2, 6:3) | details | 18.08.2019 |
| Semi-finals | Nguyen D. | Arevalo M. | 2:1 (6:4, 4:6, 7:63) | details | 17.08.2019 |
USA: Memphis - Singles - Main |
| Semi-finals | Cid Subervi R. | Nguyen D. | 2:1 (6:4, 4:6, 6:2) | details | 16.08.2019 |
| Quarter-finals | King K. | Nguyen D. | 0:2 (4:6, 3:6) | details | 16.08.2019 |
| 1/8-finals | Caruana L. | Nguyen D. | 0:2 (4:6, 67:7) | details | 14.08.2019 |
| 1/16-finals | Peck J. | Nguyen D. | 0:0 RET. (3:5) | details | 13.08.2019 |
Canada: Winnipeg - Singles - Main |
| Semi-finals | Schnur B. | Nguyen D. | 2:0 (6:2, 7:5) | details | 13.07.2019 |
| Quarter-finals | Nguyen D. | Hoang A. | 2:1 (7:65, 4:6, 6:3) | details | 12.07.2019 |
| 1/8-finals | Nguyen D. | Couacaud E. | 2:1 (1:6, 6:3, 6:2) | details | 11.07.2019 |
| 1/16-finals | Soeda G. | Nguyen D. | 0:1 RET. (3:6) | details | 11.07.2019 |
| 1/32-finals | Galarneau A. | Nguyen D. | 1:2 (6:1, 1:6, 5:7) | details | 10.07.2019 |
USA: Columbus 2 - Singles - Main |
| 1/16-finals | Nguyen D. | Kwiatkowski T. S. | 1:2 (6:4, 2:6, 4:6) | details | 11.06.2019 |
| 1/32-finals | Nguyen D. | Brouwer G. | 2:1 (6:4, 65:7, 7:5) | details | 10.06.2019 |
USA: Little Rock - Singles - Main |
| 1/8-finals | Shane R. | Nguyen D. | 2:1 (3:6, 6:3, 6:4) | details | 07.06.2019 |
| 1/16-finals | Nguyen D. | Peliwo F. | 2:1 (4:6, 6:1, 6:0) | details | 05.06.2019 |
| 1/32-finals | Nguyen D. | King K. | 2:1 (6:2, 65:7, 6:3) | details | 04.06.2019 |
USA: Sarasota - Singles - Main |
| 1/32-finals | Nguyen D. | Shane R. | 0:2 (65:7, 5:7) | details | 15.04.2019 |
China: Zhangjiagang - Singles - Main |
| 1/16-finals | Nguyen D. | Giustino L. | 0:2 (0:6, 3:6) | details | 19.03.2019 |
| 1/32-finals | Banes M. | Nguyen D. | 0:2 (4:6, 3:6) | details | 18.03.2019 |
Japan: Yokohama - Singles - Main |
| 1/16-finals | Sugita Y. | Nguyen D. | 2:1 (2:6, 6:4, 7:5) | details | 26.02.2019 |
| 1/32-finals | Ellis B. | Nguyen D. | 1:2 (6:3, 5:7, 5:7) | details | 25.02.2019 |
Mexico: Morelos - Singles - Main |
| 1/32-finals | Lopez Villasenor G. | Nguyen D. | 2:0 (6:3, 6:3) | details | 18.02.2019 |
India: Chennai - Singles - Main |
| 1/32-finals | Nguyen D. | Altmaier D. | 0:2 (3:6, 2:6) | details | 04.02.2019 |
Australia: Launceston - Singles - Main |
| 1/16-finals | Martinez P. | Nguyen D. | 2:0 (7:5, 7:62) | details | 29.01.2019 |
| 1/32-finals | Nguyen D. | Kelly D. | 2:1 (6:3, 2:6, 7:5) | details | 28.01.2019 |
Vietnam: Da Nang - Singles - Main |
| 1/16-finals | Yang T. | Nguyen D. | 2:0 (6:3, 6:4) | details | 08.01.2019 |
| 1/32-finals | Gabashvili T. | Nguyen D. | 0:2 (2:6, 4:6) | details | 07.01.2019 |
USA: M25 Los Angeles - Singles - Main |
| Quarter-finals | Holt B. | Nguyen D. | 2:0 (6:4, 6:2) | details | 04.01.2019 |
| 1/8-finals | Nguyen D. | Lebedev A. | 2:0 (7:64, 6:4) | details | 03.01.2019 |
| 1/16-finals | Gautier A. | Nguyen D. | 0:2 (1:6, 2:6) | details | 01.01.2019 |
Japan: Yokohama - Singles - Main |
| 1/8-finals | Nguyen D. | Robert S. | 0:2 (5:7, 0:6) | details | 01.03.2018 |
| 1/16-finals | Nguyen D. | Watanuki Y. | 2:0 (6:2, 6:4) | details | 27.02.2018 |
USA: US Open - Singles - Qualification |
| Quarter-finals | King D. | Nguyen D. | 2:0 (6:2, 6:1) | details | 23.08.2017 |
USA: Lexington - Singles - Main |
| Quarter-finals | Nguyen D. | Mmoh M. | 0:2 (5:7, 1:6) | details | 05.08.2017 |
| 1/8-finals | McGee J. | Nguyen D. | 1:2 (6:3, 3:6, 4:6) | details | 03.08.2017 |
| 1/16-finals | Nguyen D. | Statham J. R. | 2:1 (1:6, 7:5, 6:4) | details | 01.08.2017 |
USA: Binghamton - Singles - Main |
| 1/8-finals | Nguyen D. | Norrie C. | 0:2 (3:6, 3:6) | details | 26.07.2017 |
| 1/16-finals | Holt B. | Nguyen D. | 1:2 (3:6, 6:2, 3:6) | details | 25.07.2017 |