stadio: Cancha 2 Round: 25 Ground: Clay
| Challenger San Luis Potosi | 2018/03/27 18:00 | Daniel Elahi Galan v Joao Souza | 6-7,7-6,7-5 |
| ATP Miami Qual. | 2018/03/19 15:35 | Ruben Bemelmans v Joao Souza | 7-5,6-3 |
| Challenger Santiago | 2018/03/06 17:50 | Joao Souza v Carlos Gomez-Herrera | 3-6,1-6 |
| Challenger Santiago - Qual. | 2018/03/05 14:00 | Joao Souza v Pedro Cachin | 5-7,6-7 |
| Challenger Santiago - Qual. | 2018/03/04 15:50 | Joao Souza v Victor Nunez | 6-2,6-1 |
| Challenger Santiago - Qual. | 2018/03/03 17:40 | Joao Souza v Martin Cuevas | 6-3,2-6,6-4 |
| ATP Rio de Janeiro - Qual. | 2018/02/17 20:45 | Carlos Berlocq v Joao Souza | 6-1,7-5 |
| ATP Buenos Aires - Qual. | 2018/02/10 14:00 | Joao Souza v Gastao Elias | 6-4,3-6,0-6 |
| Coppa Davis | 2018/04/06 21:20 | Daniel Elahi Galan v Guilherme Clezar | 3-6,6-2,6-1 |
| Challenger Santiago | 2018/03/05 18:55 | Guilherme Clezar v Thomaz Bellucci | View |
| ATP San Paolo | 2018/03/01 18:05 | Albert Ramos-Vinolas v Guilherme Clezar | 6-3,6-4 |
| ATP San Paolo | 2018/02/28 02:05 | Guilherme Clezar v Thiago Monteiro | 6-3,1-6,7-5 |
| ATP San Paolo - Qual. | 2018/02/25 16:10 | Pedro Sakamoto v Guilherme Clezar | 2-6,1-6 |
| ATP San Paolo - Qual. | 2018/02/24 19:20 | Fernando Yamacita v Guilherme Clezar | 1-6,6-7 |
| ATP Rio de Janeiro - Qual. | 2018/02/17 18:00 | Guilherme Clezar v Alessandro Giannessi | 7-6,4-6,3-6 |
| ATP Buenos Aires - Qual. | 2018/02/11 16:00 | Rogerio Dutra Silva v Guilherme Clezar | 7-6,7-6 |