Stadium: Court 4 Round: 44 Ground: Clay
| ITF M25 Poznan | 2021/08/22 08:00 | Oscar Weightman v Ivan Kazakov | 6-3,2-6,1-10 |
| ITF M15 Warmbad-Villach | 2021/08/16 07:00 | Ivan Kazakov v Gonzalo Achondo | 6-3,0-6,8-10 |
| ITF M15 Antalya | 2021/06/27 06:30 | Ivan Kazakov v Stefanos Sakellaridis | 1-6,4-6 |
| ITF M15 Antalya | 2021/06/20 07:00 | Ivan Kazakov v Ray Ho | 2-6,1-6 |
| ITF M15 Tbilisi | 2021/05/18 05:30 | Aleksandr Braynin v Ivan Kazakov | 6-2,6-2 |
| ITF M15 Tbilisi | 2021/05/17 05:30 | Ivan Kazakov v Roman Nashatyrkin | 6-1,6-1 |
| ITF M15 Tbilisi | 2021/05/16 06:00 | Egor Baklanov v Ivan Kazakov | 6-7,6-3,1-10 |
| ITF M15 Antalya | 2021/04/18 07:00 | Leopold Zima v Ivan Kazakov | 6-0,6-3 |
| ITF M25 Poznan | 2021/08/22 08:00 | Thijmen Loof v Flemming Peters | 5-7,3-6 |
| ITF M15 Oldenzaal | 2021/08/15 07:30 | Zachary Eisinga v Flemming Peters | 6-0,6-3 |
| ITF M15 Sarajevo | 2021/05/30 10:30 | Matej Galik v Flemming Peters | 6-1,4-6,10-8 |
| ITF M25 Kiseljak | 2021/05/24 12:15 | Lilian Breut v Flemming Peters | 2-6,6-3,10-7 |
| ITF M25 Kiseljak | 2021/05/23 13:15 | Flemming Peters v Maxim Krapivin | 3-6,7-5,10-6 |
| ITF M15 Troisdorf | 2021/05/10 08:00 | Flemming Peters v Sidane Pontjodikromo | 4-6,1-6 |
| ITF M15 Troisdorf | 2021/05/09 08:00 | Maurus Malgiaritta v Flemming Peters | 6-2,3-6,8-10 |
| ITF M15 Antalya | 2021/05/04 07:00 | Flemming Peters v Karl Friberg | 3-6,5-7 |