Stadium: Court 13 Round: 15 Ground: Clay
| Challenger Aix en Provence | 2020/09/12 09:55 | Danilo Petrovic v Oscar Otte | 3-6,2-6 |
| Challenger Budapest | 2019/02/06 13:20 | Danilo Petrovic v Oscar Otte | 6-7,6-3,6-7 |
| Challenger Rome | 2021/04/29 08:00 | Danilo Petrovic v Flavio Cobolli | 2-6,2-6 |
| Challenger Rome | 2021/04/27 09:30 | Danilo Petrovic v Igor Sijsling | 6-1,7-6 |
| ATP Belgrade | 2021/04/19 17:00 | John Millman v Danilo Petrovic | 7-5,6-4 |
| Challenger Belgrade | 2021/04/14 08:45 | Marco Trungelliti v Danilo Petrovic | 6-3,6-2 |
| Challenger Split | 2021/04/09 09:00 | Danilo Petrovic v Andrea Collarini | 2-6,3-6 |
| Challenger Split | 2021/04/07 09:00 | Danilo Petrovic v Maximilian Marterer | 6-1,6-3 |
| Challenger Split | 2021/04/05 12:10 | Danilo Petrovic v Lukas Rosol | 6-1,6-3 |
| Challenger Marbella | 2021/03/30 15:35 | Danilo Petrovic v Nikola Milojevic | 6-3,3-6,4-6 |
| Challenger Ostrava | 2021/04/27 12:10 | Gregoire Barrere v Oscar Otte | 7-6,7-5 |
| Challenger Ostrava | 2021/04/26 10:50 | Oscar Otte v Adam Pavlasek | 6-2,6-4 |
| Challenger Ostrava | 2021/04/25 12:40 | Oscar Otte v Thomaz Bellucci | 6-4,6-3 |
| Challenger Belgrade | 2021/04/13 08:00 | Oscar Otte v Hamad Medjedovic | 3-6,6-1,3-6 |
| Challenger Oeiras | 2021/04/08 15:50 | Oscar Otte v Goncalo Oliveira | 4-6,6-4,3-6 |
| Challenger Oeiras | 2021/04/06 09:00 | Oscar Otte v Pedro Araujo | 6-2,6-4 |
| Challenger Oeiras | 2021/03/29 13:50 | Oscar Otte v Marco Trungelliti | 3-6,4-6 |
| Challenger Lille | 2021/03/24 10:30 | Giulio Zeppieri v Oscar Otte | 7-6,6-3 |