| Challenger Banja Luka | 09/11 12:15 | 25 | [199] Dutra Silva, Rogerio v Clezar, Guilherme [403] | 3-6,1-6 | |
| Challenger Banja Luka | 09/10 08:00 | 24 | [292] Jelle Sels v Clezar, Guilherme [403] | 2-6,3-6 | |
| La Marsa, Singles M-ITF-TUN-37A | 09/07 09:30 | 28 | [392] Clezar, Guilherme v Louis Wessels [366] | 6-1,3-6,3-6 | |
| La Marsa, Singles M-ITF-TUN-37A | 09/06 13:00 | 27 | [300] Manuel Guinard v Clezar, Guilherme [392] | 3-6,2-6 | |
| La Marsa, Singles M-ITF-TUN-37A | 09/05 12:00 | 26 | [463] Michael Geerts v Clezar, Guilherme [392] | 5-7,1-6 | |
| La Marsa, Singles M-ITF-TUN-37A | 09/03 13:30 | 25 | Pietro Marino v Clezar, Guilherme | 1-6,3-6 | |
| Irpin, Singles Qualifying M-ITF-UKR-05A | 08/31 08:00 | 28 | Denis Yevseyev v Clezar, Guilherme | 2-6,6-3,6-4 | |
| Irpin, Singles Qualifying M-ITF-UKR-05A | 08/30 08:00 | 27 | [392] Clezar, Guilherme v Genaro Alberto Olivieri [492] | 4-6,7-5,6-4 | |
| Irpin, Singles Qualifying M-ITF-UKR-05A | 08/29 08:00 | 26 | Clezar, Guilherme v Alexander Weis | 6-2,6-3 | |
| Irpin, Singles Qualifying M-ITF-UKR-05A | 08/28 07:30 | 25 | Clezar, Guilherme v Parshutin, Denis | 6-0,6-1 | |
| L'Aquila, Italie | 08/24 16:30 | 27 | [137] Martin, Andrej v Clezar, Guilherme [431] | 3-6,7-6,6-4 | |
| L'Aquila, Italie | 08/22 09:40 | 26 | [271] Facundo Mena v Clezar, Guilherme [431] | 7-6,4-6,4-6 | |
| L'Aquila, Italie | 08/21 12:20 | 25 | [431] Clezar, Guilherme v Aslan Karatsev [260] | 7-5,6-4 | |
| L'Aquila, Italie | 08/20 08:00 | 24 | [431] Clezar, Guilherme v Pavic, Ante [122] | 6-3,6-2 | |
| L'Aquila, Italie | 08/20 08:00 | 24 | Clezar, Guilherme v Ulises Blanch | Cancelled | |
| Cordenons, Italy | 08/14 18:20 | 25 | [118] Lorenzi, Paolo v Clezar, Guilherme [359] | 2-6,7-5,7-6 | |
| Cordenons, Italy | 08/13 08:00 | 24 | [295] Reboul, Fabien v Clezar, Guilherme [359] | 2-6,2-6 | |
| Challenger Tampere | 07/25 09:00 | 26 | [304] Clezar, Guilherme v Krstin, Pedja [244] | 6-7,1-6 | |
| Challenger Tampere | 07/24 07:30 | 25 | [160] Federico Gaio v Clezar, Guilherme [304] | 3-6,5-7 | |
| Challenger Tampere | 07/22 09:00 | 24 | [304] Clezar, Guilherme v Zsombor Piros [362] | 6-3,6-4 | |
| Challenger Amersfoort | 07/18 09:00 | 26 | [149] Pedro Martinez v Clezar, Guilherme [309] | 7-6,6-2 | |
| Challenger Amersfoort | 07/17 08:00 | 25 | [309] Clezar, Guilherme v Kamke, Tobias [224] | 6-2,6-2 | |
| Challenger Amersfoort | 07/15 14:05 | 24 | [296] Frederico Ferreira Silva v Clezar, Guilherme [309] | 5-7,1-6 | |
| Challenger Perugia | 07/11 13:45 | 26 | [262] Quinzi, Gianluigi v Clezar, Guilherme [322] | 6-3,4-6,7-6 | |
| Challenger Perugia | 07/10 14:30 | 25 | [322] Clezar, Guilherme v Damir Dzumhur [91] | 6-4,3-6,6-4 | |
| Challenger Perugia | 07/09 08:00 | 24 | [322] Clezar, Guilherme v Pavel Kotov [275] | 6-3,3-6,6-3 | |
| Challenger Perugia | 07/08 09:00 | 166 | [295] Grigelis, Laurynas v Clezar, Guilherme [322] | 6-4,6-7,1-6 | |
| Ludwigshafen, Allemagne | 07/01 16:25 | 24 | [276] Gian Marco Moroni v Clezar, Guilherme [322] | 6-3,3-6,7-5 | |
| Milan, Italy | 06/24 09:00 | 24 | [295] Nino Serdarusic v Clezar, Guilherme [321] | 7-6,6-4 | |
| Parma II, Italy | 06/19 08:00 | 25 | [290] Clezar, Guilherme v Andrea Pellegrino [356] | 7-5,6-7,4-6 |