| ITF Spain F13 | 2014/06/14 14:55 | Frederik Nielsen v David Perez Sanz | 6-4,6-1 |
| UTR Pro Tennis Series Hillerod | 2022/02/19 11:45 | Lorenzo Bocchi v David Perez Sanz | 1-0 |
| UTR Pro Tennis Series Hillerod | 2022/02/18 11:00 | David Perez Sanz v Nikolaj Katic | 6-2,7-6 |
| UTR Pro Tennis Series Hillerod | 2022/02/17 15:19 | David Perez Sanz v Felipe Mikkelsen | 6-4,5-0 |
| UTR Pro Tennis Series Hillerod | 2022/02/16 17:00 | Ricardo Villacorta-Alonso v David Perez Sanz | 2-6,6-7 |
| UTR Pro Tennis Series Hillerod | 2022/02/15 15:30 | Ivan Penev v David Perez Sanz | 4-6,4-6 |
| UTR Pro Tennis Series Plovdiv | 2022/02/12 11:30 | David Perez Sanz v Egor Agafonov | 2-6,4-6 |
| UTR Pro Tennis Series Plovdiv | 2022/02/11 12:00 | David Perez Sanz v Vladyslav Manafov | 3-6,4-5 |
| UTR Pro Tennis Series Plovdiv | 2022/02/10 08:40 | David Perez Sanz v Ivan Liutarevich | 4-6,1-5 |
| UTR Pro Tennis Series Hillerod | 2022/02/19 09:02 | Yanais Laurent v Frederik Nielsen | 6-7,6-3,5-6 |
| UTR Pro Tennis Series Hillerod | 2022/02/18 12:30 | Jurriaan Bol v Frederik Nielsen | 5-7,7-6,3-5 |
| UTR Pro Tennis Series Hillerod | 2022/02/17 14:05 | Alexander Stage v Frederik Nielsen | 3-6,1-5 |
| UTR Pro Tennis Series Hillerod | 2022/02/16 15:00 | Sergio Redondo v Frederik Nielsen | 0-6,1-6 |
| UTR Pro Tennis Series Hillerod | 2022/02/14 11:00 | Kevin Chahoud v Frederik Nielsen | 6-4,6-7,0-6 |
| ATP Doha | 2021/03/06 09:00 | Frederik Nielsen v Ramkumar Ramanathan | 4-6,1-6 |
| Tennis Point Exhibition Series | 2020/07/18 11:35 | Sebastian Mortier v Frederik Nielsen | 4-6,3-6 |
| Tennis Point Exhibition Series | 2020/07/17 09:25 | Sebastian Fanselow v Frederik Nielsen | 6-3,6-7,2-6 |