USA: Edwardsville - Singles - Main |
| Quarter-finals | Geller A. | Boltz S. | 2:0 (6:4, 6:4) | details | 10.08.2018 |
| 1/8-finals | Andrade A. | Boltz S. | 0:2 (3:6, 3:6) | details | 09.08.2018 |
| 1/16-finals | Johnson T. A. | Boltz S. | 1:2 (6:4, 2:6, 3:6) | details | 08.08.2018 |
USA: Decatur - Singles - Main |
| 1/8-finals | Alvarez N. | Boltz S. | 2:1 (4:6, 7:65, 6:1) | details | 02.08.2018 |
| 1/16-finals | Smith K. | Boltz S. | 0:2 (4:6, 60:7) | details | 01.08.2018 |
USA: Champaign - Singles - Main |
| 1/8-finals | McNally J. | Boltz S. | 2:1 (3:6, 6:1, 6:4) | details | 25.07.2018 |
| 1/16-finals | Chappell N. | Boltz S. | 0:2 (4:6, 5:7) | details | 24.07.2018 |
USA: Iowa City - Singles - Main |
| Quarter-finals | Karlovskiy E. | Boltz S. | 2:1 (3:6, 7:5, 6:3) | details | 20.07.2018 |
| 1/8-finals | Iradukunda G. | Boltz S. | 0:2 (2:6, 65:7) | details | 19.07.2018 |
| 1/16-finals | Soderlund C. | Boltz S. | 0:2 (64:7, 68:7) | details | 18.07.2018 |
Spain: Bakio - Singles - Main |
| 1/16-finals | Davidovich Fokina A. | Boltz S. | 2:0 (6:2, 6:1) | details | 03.07.2018 |
Spain: Palma Del Rio - Singles - Main |
| 1/8-finals | Vivero G. P. | Boltz S. | 2:0 (6:4, 7:63) | details | 27.06.2018 |
| 1/16-finals | Minin M. | Boltz S. | 1:2 (67:7, 6:2, 1:6) | details | 26.06.2018 |
Spain: Santa Margarida de Montbui - Singles - Main |
| 1/16-finals | Boltz S. | Mas De Ugarte J. | 0:2 (3:6, 3:6) | details | 29.05.2018 |
Germany: Kaarst - Singles - Main |
| Semi-finals | Moeller M. | Boltz S. | 2:0 (6:4, 6:4) | details | 03.02.2018 |
| Quarter-finals | Kern R. | Boltz S. | 1:2 (3:6, 7:64, 3:6) | details | 02.02.2018 |
| 1/8-finals | Boltz S. | Michnev P. | 2:0 (6:3, 6:4) | details | 01.02.2018 |
| 1/16-finals | Boltz S. | Diarra G. | 2:0 (6:2, 6:1) | details | 31.01.2018 |
Germany: Schwieberdingen - Singles - Main |
| 1/8-finals | Authom M. | Boltz S. | 2:0 (6:4, 6:4) | details | 11.01.2018 |
| 1/16-finals | Boltz S. | Olivetti A. | 2:1 (3:6, 7:5, 6:3) | details | 09.01.2018 |
United Kingdom: Shrewsbury - Singles - Main |
| 1/8-finals | Boltz S. | Horansky F. | 0:2 (64:7, 0:6) | details | 15.02.2017 |
| 1/16-finals | Boltz S. | Clarke J. | 2:1 (3:6, 6:3, 6:4) | details | 14.02.2017 |
Germany: Karlsruher - Singles - Main |
| 1/8-finals | Cid Subervi R. | Boltz S. | 2:0 (6:3, 6:2) | details | 18.08.2016 |
| 1/16-finals | Ruetzel T. A. | Boltz S. | 0:2 (67:7, 4:6) | details | 16.08.2016 |
Spain: Bejar - Singles - Main |
| 1/8-finals | Boltz S. | Reinwein S. | 0:2 (2:6, 3:6) | details | 04.08.2016 |
| 1/16-finals | Boltz S. | Numajiri K. | 2:0 (6:2, 7:5) | details | 03.08.2016 |
Germany: Nussloch - Singles - Main |
| 1/16-finals | Ignatik U. | Boltz S. | 2:1 (4:6, 6:4, 6:4) | details | 26.01.2016 |
Germany: Kaarst - Singles - Main |
| 1/16-finals | Simon T. | Boltz S. | 2:0 (6:3, 6:4) | details | 19.01.2016 |
Germany: Schwieberdingen - Singles - Main |
| 1/8-finals | Boltz S. | Michnev P. | 1:2 (1:6, 7:65, 1:6) | details | 14.01.2016 |
| 1/16-finals | Boltz S. | Venturino T. | 2:0 (7:5, 6:1) | details | 12.01.2016 |
France: Mouilleron-Le-Captif - Singles - Main |
| 1/16-finals | Boltz S. | Mertl J. | 0:2 (4:6, 4:6) | details | 09.11.2015 |
France: Brest - Singles - Main |
| 1/8-finals | Boltz S. | Vanni L. | 0:2 (5:7, 2:6) | details | 22.10.2015 |
| 1/16-finals | Caruso S. | Boltz S. | 0:2 (65:7, 3:6) | details | 20.10.2015 |
France: Rennes - Singles - Main |
| 1/16-finals | Boltz S. | Copil M. | 0:2 (5:7, 2:6) | details | 13.10.2015 |
France: St. Remy - Singles - Main |
| Quarter-finals | Boltz S. | Dodig I. | 1:2 (2:6, 6:4, 3:6) | details | 11.09.2015 |
| 1/8-finals | Lacko L. | Boltz S. | 1:2 (4:6, 6:1, 3:6) | details | 10.09.2015 |
| 1/16-finals | Boltz S. | Karatsev A. | 2:0 (6:0, 6:4) | details | 09.09.2015 |
Italy: Piombino - Singles - Main |
| Semi-finals | Halys Q. | Boltz S. | 2:0 (6:3, 7:65) | details | 28.08.2015 |
| Quarter-finals | Boltz S. | Marsalek J. | 2:0 (6:2, 6:4) | details | 27.08.2015 |
| 1/8-finals | Boltz S. | Zormann Da Silva M. | 2:0 (6:2, 6:4) | details | 26.08.2015 |
| 1/16-finals | Boltz S. | Miccini G. | 2:0 (6:2, 6:4) | details | 25.08.2015 |
Spain: Segovia - Singles - Main |
| 1/16-finals | Mertens Y. | Boltz S. | 2:0 (6:4, 6:2) | details | 04.08.2015 |
Kazakhstan: Astana - Singles - Main |
| 1/16-finals | Boltz S. | Popko D. | 0:2 (4:6, 4:6) | details | 28.07.2015 |
Italy: Recanati - Singles - Main |
| 1/16-finals | Berankis R. | Boltz S. | 2:1 (5:7, 6:2, 6:2) | details | 21.07.2015 |
France: Quimper - Singles - Main |
| 1/8-finals | Marchenko I. | Boltz S. | 2:1 (3:6, 6:4, 6:0) | details | 04.03.2015 |
| 1/16-finals | Lokoli L. | Boltz S. | 0:2 (1:6, 2:6) | details | 03.03.2015 |
Germany: Stuttgart-Stammheim - Singles - Main |
| Semi-finals | Boltz S. | Marterer M. | 0:2 (4:6, 4:6) | details | 17.01.2015 |