Stadium: Court 1 Round: 27 Ground: Clay
| ITF M25 Meerbusch | 2021/04/15 10:00 | Markus Eriksson v Milan Welte | 3-6,1-6 |
| ITF M25 Meerbusch | 2021/04/14 12:15 | Milan Welte v Pietro Rondoni | 6-3,4-6,6-4 |
| ITF M25 Meerbusch | 2021/04/13 13:30 | Mats Rosenkranz v Milan Welte | 2-6,2-6 |
| ITF M25 Meerbusch | 2021/04/12 11:00 | Hendrik Jebens v Milan Welte | 5-7,1-6 |
| ITF M25 Meerbusch | 2021/04/11 13:30 | Jannik Rother v Milan Welte | 2-6,2-6 |
| ITF M25 Biel | 2021/03/29 13:35 | Milan Welte v Jakub Paul | 4-6,1-6 |
| ITF M15 Rovinj | 2021/03/16 09:00 | Milan Welte v Federico Arnaboldi | 2-6,2-6 |
| ITF M15 Rovinj | 2021/03/15 11:30 | Sebastian Prechtel v Milan Welte | 6-1,4-6,1-10 |
| ITF M25 Meerbusch | 2021/04/15 10:00 | Alexander Erler v Yannick Mertens | 6-3,3-6,6-1 |
| ITF M25 Meerbusch | 2021/04/14 10:30 | Alexander Erler v Marvin Netuschil | 6-3,6-2 |
| ITF M25 Biel | 2021/03/30 08:00 | Alexander Erler v Kilian Feldbausch | 4-6,6-3,5-10 |
| ITF M25 Biel | 2021/03/29 08:00 | Alexander Erler v Mischa Lanz | 6-3,6-4 |
| Challenger Lugano | 2021/03/21 11:50 | Tim Van Rijthoven v Alexander Erler | 7-6,6-0 |
| ITF M25 Trimbach | 2021/03/12 09:55 | Elmar Ejupovic v Alexander Erler | 7-6,6-7,6-3 |
| ITF M25 Trimbach | 2021/03/11 10:00 | Quentin Folliot v Alexander Erler | 4-6,3-6 |
| ITF M25 Trimbach | 2021/03/09 14:40 | Yannik Steinegger v Alexander Erler | 4-6,4-6 |