USA: Sioux Falls - Singles - Qualification |
| Final | Borisiouk M. | Montsi S. | 2:0 (6:3, 6:3) | details | 21.10.2024 |
| Semi-finals | Montsi S. | Wiskandt M. | 2:0 (6:2, 6:4) | details | 20.10.2024 |
USA: M15 Norman, OK - Singles - Main |
| 1/16-finals | Montsi S. | Bigun K. | 1:2 (61:7, 6:3, 4:6) | details | 25.10.2023 |
Rwanda: M25 Kigali 2 - Singles - Main |
| 1/8-finals | Dev S D P. | Montsi S. | 2:0 (6:0, 6:3) | details | 14.09.2023 |
| 1/16-finals | Montsi S. | Madan T. | 2:0 (6:4, 6:3) | details | 13.09.2023 |
USA: M25 Decatur, IL - Singles - Main |
| 1/16-finals | Montsi S. | Ward E. | 1:2 (7:5, 3:6, 3:6) | details | 04.08.2022 |
USA: M25 Champaign, IL - Singles - Main |
| 1/16-finals | Montsi S. | Kingsley C. | 0:2 (5:7, 1:6) | details | 20.07.2022 |
USA: M25 Decatur, IL - Singles - Main |
| 1/16-finals | Montsi S. | Rybakov A. | CAN. | details | 04.08.2021 |
USA: M25 Champaign, IL - Singles - Main |
| 1/8-finals | Peck J. | Montsi S. | 2:1 (6:3, 65:7, 6:4) | details | 29.07.2021 |
| 1/16-finals | Montsi S. | Schoolkate T. | 2:0 (6:4, 6:4) | details | 28.07.2021 |
USA: M15 Edwardsville, IL - Singles - Main |
| 1/8-finals | Jubb P. | Montsi S. | 1:1 RET. (2:6, 6:3, 3:1) | details | 22.07.2021 |
| 1/16-finals | Montsi S. | Bernard A. | 2:1 (6:0, 5:7, 6:3) | details | 21.07.2021 |
USA: M15 Champaign, IL - Singles - Main |
| 1/8-finals | Pervolarakis M. | Montsi S. | 2:1 (4:6, 6:3, 6:4) | details | 24.06.2021 |
| 1/16-finals | Montsi S. | Lilov V. | 2:0 (6:4, 6:1) | details | 23.06.2021 |
USA: M25 Champaign, IL 2 - Singles - Main |
| 1/16-finals | Chappell N. | Montsi S. | 2:0 (7:5, 6:2) | details | 10.09.2019 |
USA: M15 Champaign, IL - Singles - Main |
| 1/8-finals | Geller A. | Montsi S. | 2:0 (6:4, 6:2) | details | 26.07.2019 |
| 1/16-finals | Montsi S. | Dougaz A. | 2:0 (6:4, 6:3) | details | 23.07.2019 |
USA: M25 Champaign, IL - Singles - Main |
| 1/16-finals | Gomes G. | Montsi S. | 2:1 (3:6, 6:2, 7:63) | details | 05.06.2019 |
USA: Tucson - Singles - Main |
| 1/16-finals | Montsi S. | Glasspool L. | 1:2 (4:6, 6:3, 3:6) | details | 09.01.2019 |
Australia: Australian Open - Singles - Main |
| 1/32-finals | Bass F. | Montsi S. | 2:0 (6:2, 6:4) | details | 21.01.2017 |
USA: M15 Norman, OK - Doubles - Main |
| Quarter-finals | Montsi K./Montsi S. | Catry R./Van Sambeek F. | 0:2 (4:6, 3:6) | details | 26.10.2023 |
| 1/8-finals | Ribero F./Valiev I. | Montsi K./Montsi S. | 0:2 (4:6, 4:6) | details | 24.10.2023 |
Rwanda: M25 Kigali 2 - Doubles - Main |
| 1/8-finals | Bassem Sobhy M./Reddy R. | Hakizumwami J./Montsi S. | 2:1 (7:64, 5:7, 13:11) | details | 12.09.2023 |
USA: M25 Decatur, IL - Doubles - Main |
| Quarter-finals | Kenyatte K./Montsi S. | Brouwer G./Stalder R. | 0:2 (65:7, 3:6) | details | 05.08.2021 |
| 1/8-finals | Takahashi Y./Yamasaki J. | Kenyatte K./Montsi S. | 1:2 (2:6, 7:5, 9:11) | details | 03.08.2021 |
USA: M25 Champaign, IL - Doubles - Main |
| 1/8-finals | Kenyatte K./Montsi S. | Schoolkate T./Sweeny D. | 0:2 (3:6, 63:7) | details | 27.07.2021 |
USA: M15 Edwardsville, IL - Doubles - Main |
| Semi-finals | Meister N./Montsi S. | Kuzuhara B./Langmo C. | 0:2 (4:6, 3:6) | details | 23.07.2021 |
| Quarter-finals | Marcondes I./Zhu E. | Meister N./Montsi S. | 0:2 (4:6, 4:6) | details | 22.07.2021 |
| 1/8-finals | Meister N./Montsi S. | Calero J./Marchan H. | 2:0 (6:3, 6:3) | details | 20.07.2021 |
USA: M15 Champaign, IL - Doubles - Main |
| Final | Bass F./Hands T. | Kenyatte K./Montsi S. | 2:0 (7:5, 6:4) | details | 26.06.2021 |
| Semi-finals | Kirkov V./Ponwith N. | Kenyatte K./Montsi S. | 1:2 (3:6, 6:3, 8:10) | details | 25.06.2021 |
| Quarter-finals | Kenyatte K./Montsi S. | Pereira J./Villanueva G. | WO. | details | 25.06.2021 |
| 1/8-finals | Jachuck R./Schachter N. | Kenyatte K./Montsi S. | 0:2 (2:6, 64:7) | details | 22.06.2021 |
Australia: Australian Open - Doubles - Main |
| 1/16-finals | Efstathiou M./Neos E. | Boyer T./Montsi S. | 2:0 (7:65, 7:63) | details | 22.01.2017 |