Stadium: Court Smart Trade Round: 14 Ground: Clay
| Challenger - Biella | 2021/05/30 13:30 | Ronald Slobodchikov v Camilo Ugo Carabelli | 2-6,1-6 |
| Challenger - Oeiras | 2021/05/23 10:00 | Lucas Catarina v Ronald Slobodchikov | 6-1,6-3 |
| UTR Pro Tennis Series - Barcelona | 2021/05/02 07:00 | Ronald Slobodchikov v Yurii Dzhavakian | 4-6,2-6 |
| UTR Pro Tennis Series - Barcelona | 2021/04/28 09:30 | Ronald Slobodchikov v Pol Toledo Bague | 2-6,2-6 |
| UTR Pro Tennis Series - Barcelona | 2021/04/27 09:30 | Ronald Slobodchikov v Noah Lopez | 2-6,4-6 |
| UTR Pro Tennis Series - Barcelona | 2021/04/26 09:30 | Fermin Calvo Barcelo v Ronald Slobodchikov | 4-6,3-6 |
| Challenger - Oeiras - Kwal. | 2021/04/04 13:10 | Alexey Vatutin v Ronald Slobodchikov | 6-2,6-3 |
| ITF M15 La Nucia | 2021/03/11 11:40 | Ronald Slobodchikov v Pablo Llamas Ruiz | 2-6,1-6 |
| UTR Pro Tennis Series - Barcelona | 2021/06/12 11:30 | Marcelo Zormann v Oscar Jose Gutierrez | 3-0 |
| UTR Pro Tennis Series - Barcelona | 2021/06/11 11:00 | Bruno P Navarro v Oscar Jose Gutierrez | 6-7,4-6 |
| UTR Pro Tennis Series - Barcelona | 2021/06/10 09:30 | Pol Amoros Ramos v Oscar Jose Gutierrez | 4-6,7-6,2-5 |
| UTR Pro Tennis Series - Barcelona | 2021/06/09 08:00 | Jose Joaquin M Cisneros v Oscar Jose Gutierrez | 2-6,2-5 |
| UTR Pro Tennis Series - Barcelona | 2021/06/07 12:30 | Oriol Roca Batalla v Oscar Jose Gutierrez | 4-6,6-4,3-6 |
| UTR Pro Tennis Series Boekarest | 2021/06/06 06:00 | Oscar Jose Gutierrez v Stefan Palosi | 7-5,4-6,2-6 |
| UTR Pro Tennis Series Boekarest | 2021/06/05 07:00 | Juan Pablo Paz v Oscar Jose Gutierrez | 3-6,1-6 |
| UTR Pro Tennis Series Boekarest | 2021/06/04 10:00 | Oscar Jose Gutierrez v Kuzey Cekirge | 6-3,6-2 |