Stadium: Court 4 Round: 19 Ground: Clay
| Challenger Poznan | 2021/07/25 13:25 | Thomaz Bellucci v David Poljak | 6-4,3-6,1-6 |
| ITF M25 Kottingbrunn | 2021/07/22 08:00 | Mate Valkusz v David Poljak | 6-7,7-5,7-5 |
| ITF M25 Kottingbrunn | 2021/07/20 12:10 | Niklas Waldner v David Poljak | 7-6,2-6,6-7 |
| Challenger Iasi | 2021/07/13 12:15 | Zdenek Kolar v David Poljak | 6-2,7-5 |
| Challenger Iasi | 2021/07/12 08:00 | Vlad Andrei Dancu v David Poljak | 2-6,0-6 |
| Challenger Iasi | 2021/07/11 09:20 | Mircea-Alexandru Jecan v David Poljak | 4-6,0-6 |
| ITF M25 Wroclaw | 2021/06/29 13:25 | Uladzimir Ignatik v David Poljak | 6-0,6-2 |
| ITF M15 Bergamo | 2021/06/22 15:50 | David Poljak v Dali Blanch | 2-6,6-3,3-6 |
| Challenger Poznan | 2021/07/25 10:30 | Sebastian Fanselow v Lucas Gerch | 2-6,5-7 |
| ITF M25 The Hague | 2021/07/01 09:55 | Manuel Guinard v Lucas Gerch | 6-3,6-2 |
| ITF M25 The Hague | 2021/06/29 11:20 | Lucas Gerch v Vladimir Ivanov | 6-1,6-2 |
| Challenger Forli | 2021/06/16 09:30 | Francesco Forti v Lucas Gerch | 6-4,6-4 |
| Challenger Forli | 2021/06/15 09:30 | Lucas Gerch v Thiago Agustin Tirante | 7-6,3-6,6-3 |
| Challenger Forli | 2021/06/14 09:30 | Lucas Gerch v Elmar Ejupovic | 4-6,6-4,7-6 |
| Challenger Forli | 2021/06/13 09:45 | Alessandro Bega v Lucas Gerch | 3-6,1-6 |
| ITF M15 Antalya | 2021/05/28 08:20 | Pol Martin Tiffon v Lucas Gerch | 7-5,6-3 |