Round: 62 Ground: Clay
| ITF Brazil F4 | 2017/11/26 13:00 | Reami Da Cunha, Leonardo v Gabriel P Tumasonis | 3-6,1-6 |
| ITF Brazil F3 | 2017/11/20 14:00 | Gabriel P Tumasonis v Tsuchiya, Alexandre | 1-6,4-6 |
| ITF Brazil F2 | 2017/11/14 17:40 | Ribeiro Marcondes, Igor v Gabriel P Tumasonis | 6-3,6-4 |
| ITF Brazil F2 | 2017/11/12 13:00 | Gabriel P Tumasonis v Rafael Tosetto | 6-2,6-4 |
| ITF Argentina F7 | 2017/09/11 13:00 | Severino, Carlos Eduardo v Gabriel P Tumasonis | 6-4,3-6,6-2 |
| ITF Argentina F7 | 2017/09/09 17:30 | Sierra, Fernando v Gabriel P Tumasonis | 4-6,7-5,3-6 |
| ITF Argentina F6 | 2017/09/02 14:30 | Gabriel P Tumasonis v Arus, Rodrigo | 2-6,2-6 |
| ITF Belgium F7 Qual | 2017/07/30 13:55 | Gabriel P Tumasonis v Tholl, Robi | 6-4,5-7,3-6 |