Stadium: Court 7 Round: 27 Ground: Clay
| Challenger Zagreb MD | 2021/05/14 13:00 | Golubev/Nedovyesov v Walkow/Zielinski | 7-6,6-4 |
| Challenger Zagreb MD | 2021/05/14 10:10 | Jung/Soeda v Walkow/Zielinski | 3-6,4-6 |
| Challenger Zagreb MD | 2021/05/12 08:00 | Walkow/Zielinski v Golubev/Tiurnev | 6-0,6-2 |
| Challenger Prague MD | 2021/05/04 15:40 | Walkow/Zielinski v Sabanov/Sabanov | 6-3,3-6,5-10 |
| Challenger Split MD | 2021/04/17 13:00 | Barrere/Olivetti v Walkow/Zielinski | 2-6,5-7 |
| Challenger Split MD | 2021/04/16 13:30 | Walkow/Zielinski v Golubev/Nedovyesov | 6-3,7-6 |
| Challenger Split MD | 2021/04/15 12:35 | Ajdukovic/Nincevic v Walkow/Zielinski | 0-6,4-6 |
| Challenger Split MD | 2021/04/14 13:00 | Walkow/Zielinski v Raja/Weissborn | 6-3,6-4 |