Stadium: Center Court Round: 26 Ground: Clay
| Challenger L'Aquila | 2018/06/22 13:00 | Guilherme Clezar v Gianluigi Quinzi | 6-3,1-6,7-6 |
| Challenger Vicenza | 2018/05/31 12:30 | Guilherme Clezar v Gianluigi Quinzi | 6-4,6-3 |
| Challenger Buenos Aires | 2017/03/15 14:00 | Guilherme Clezar v Gianluigi Quinzi | 2-6,5-7 |
| Challenger Caltanissetta | 2016/06/07 12:10 | Guilherme Clezar v Gianluigi Quinzi | 2-6,6-1,6-7 |
| Challenger Perugia | 2019/07/10 13:00 | Filip Horanský v Gianluigi Quinzi | 6-3,2-6,2-6 |
| Challenger Perugia | 2019/07/09 14:30 | Gianluigi Quinzi v Roberto Marcora | 6-7,6-3,6-3 |
| Challenger Ludwigshafen | 2019/07/02 16:00 | Gianluigi Quinzi v Nicola Kuhn | 6-3,6-7,3-6 |
| Challenger Parma | 2019/06/20 16:00 | Federico Gaio v Gianluigi Quinzi | 6-3,6-4 |
| Challenger Parma | 2019/06/19 11:45 | Marco Bortolotti v Gianluigi Quinzi | 1-6,3-6 |
| Challenger Vicenza | 2019/05/28 10:05 | Gianluigi Quinzi v Francesco Forti | 6-3,2-6,4-6 |
| French Open | 2019/05/22 13:05 | Gianluigi Quinzi v Manuel Guinard | 3-6,6-7 |
| French Open | 2019/05/20 10:20 | Gianluigi Quinzi v Marc Polmans | 6-2,1-6,6-3 |
| Challenger Perugia | 2019/07/10 14:30 | Guilherme Clezar v Damir Dzumhur | 6-4,3-6,6-4 |
| Challenger Perugia | 2019/07/09 08:00 | Guilherme Clezar v Pavel Kotov | 6-3,3-6,6-3 |
| Challenger Perugia | 2019/07/08 09:00 | Laurynas Grigelis v Guilherme Clezar | 6-4,6-7,1-6 |
| Challenger Ludwigshafen | 2019/07/01 16:25 | Gian Marco Moroni v Guilherme Clezar | 6-3,3-6,7-5 |
| Challenger Milán | 2019/06/24 09:00 | Nino Serdarusic v Guilherme Clezar | 7-6,6-4 |
| Challenger Parma | 2019/06/19 08:00 | Guilherme Clezar v Andrea Pellegrino | 7-5,6-7,4-6 |
| ATP Lyon | 2019/05/18 10:00 | Guilherme Clezar v Maxime Janvier | 5-7,6-4,4-6 |
| Challenger Samarkand | 2019/05/14 11:30 | Aleksandar Vukic v Guilherme Clezar | 7-5,6-4 |