Stadium: Court 4 Round: 62 Ground: Clay
| ITF Turkey F13 | 2018/03/31 11:00 | Felipe Meligeni Rodrigues Alves v Niklas Guttau | 6-3,6-1 |
| ITF Tunisia F32 | 2017/10/23 08:30 | Francois-Arthur Vibert v Niklas Guttau | 6-1,6-2 |
| ITF Tunisia F32 | 2017/10/22 08:30 | Matt McBride v Niklas Guttau | 3-6,3-6 |
| ITF Tunisia F31 | 2017/10/16 10:30 | Vlad Andrei Dancu v Niklas Guttau | 6-4,6-2 |
| ITF Tunisia F31 | 2017/10/15 08:30 | Vito Dell'Elba v Niklas Guttau | 2-6,0-6 |
| ITF Netherlands F7 | 2017/08/29 14:50 | Stephan Gerritsen v Niklas Guttau | 7-5,6-3 |
| ITF Netherlands F7 | 2017/08/27 10:00 | Niklas Guttau v Marvin Greven | 6-2,1-6,6-1 |
| ITF Netherlands F7 | 2017/08/26 08:00 | Tom Schonenberg v Niklas Guttau | 6-3,6-7,6-7 |
| ITF Turkey F13 | 2018/03/31 11:00 | Francisco Cerundolo v Lucas Hellfritsch | 6-4,6-2 |
| ITF Portugal F6 Qual | 2018/03/24 13:00 | Lucas Hellfritsch v Martim L Prata | 6-4,4-6,3-6 |
| ITF Portugal F4 | 2018/03/13 11:00 | Lucas Hellfritsch v Miliaan Niesten | 0-6,2-6 |
| ITF Portugal F4 | 2018/03/12 10:00 | Guillaume Dermiens v Lucas Hellfritsch | View |
| ITF Portugal F4 | 2018/03/10 11:00 | Lucas Hellfritsch v Loic Perret | 7-6,7-6 |
| ITF Netherlands F6 | 2017/08/19 10:00 | Tim Van Der Horst v Lucas Hellfritsch | 6-3,6-3 |
| ITF Germany F10 | 2017/08/06 08:00 | Benjamin Hassan v Lucas Hellfritsch | 6-3,6-4 |
| ITF Germany F9 | 2017/07/31 09:00 | Gavin Van Peperzeel v Lucas Hellfritsch | 7-6,6-4 |