Stadium: Court 2 Round: 25 Ground: Hardcourt outdoor
| ITF - M25 Sunderland | 2020/02/27 10:00 | Mertens, Yannick v Dan Added | 3-6,7-6,6-7 |
| ITF - M25 Sunderland | 2020/02/25 09:55 | Mertens, Yannick v Patten, Henry | 7-6,4-6,6-4 |
| Challenger - Koblenz | 2020/02/17 16:05 | Mirza Basic v Mertens, Yannick | 6-3,6-1 |
| ITF - M15 Grenoble | 2020/02/12 11:45 | Mertens, Yannick v Titouan Droguet | 7-6,4-6,4-6 |
| ITF - M15 Veigy-Foncenex | 2020/01/28 13:55 | Alexis Gautier v Mertens, Yannick | 6-2,7-6 |
| ITF - M15 Bressuire | 2020/01/23 12:10 | Mertens, Yannick v Anton Matusevich | 7-6,6-7,5-7 |
| ITF - M15 Bressuire | 2020/01/22 12:05 | Mertens, Yannick v Titouan Droguet | 6-4,6-2 |
| ITF M15 Villers Les Nancy | 2019/11/14 19:05 | Harold Mayot v Mertens, Yannick | 6-2,6-3 |
| ITF - M15 Héraklion | 2020/02/12 09:30 | Dembek, Michal v Petros Tsitsipas | 7-5,2-6,6-7 |
| ITF - M15 Antalya | 2019/12/17 07:00 | Dembek, Michal v Nedelko, Ivan | 7-6,5-7,2-6 |
| Antalya, Qualifications Simples M-ITF-TUR-33A | 2019/12/09 07:00 | Dembek, Michal v Igor Saveljic | 1-6,6-7 |
| ITF - M15 Monastir | 2019/11/27 12:40 | Dembek, Michal v Benjamin Lock | 6-7,2-6 |
| ITF M15 Prague | 2019/11/06 13:00 | Illya Beloborodko v Dembek, Michal | 6-2,7-6 |
| ITF M15 Opava | 2019/11/01 08:55 | Pospisil, Jaroslav v Dembek, Michal | 4-6,6-3,6-4 |
| ITF M15 Opava | 2019/10/31 12:30 | Dembek, Michal v Andrew Paulson | 6-4,7-6 |
| ITF M15 Opava | 2019/10/30 17:15 | Federico Arnaboldi v Dembek, Michal | 3-6,2-6 |