Stadium: Court 6 Round: 25 Ground: Hardcourt indoor
| ITF Latvia F1 | 2017/08/02 14:55 | Grinvalds, Roberts v Dijkhuizen, Marc | 1-6,4-6 |
| ITF Estonia F1 | 2018/07/16 07:00 | Solberg, Christoffer v Grinvalds, Roberts | 6-7,7-6,5-7 |
| ITF Estonia F1 | 2018/07/16 07:00 | Soyfer, Daniel v Grinvalds, Roberts | 3-6,3-6 |
| ITF Portugal F11 Qual | 2018/07/03 08:30 | Ivan Marrero Curbelo v Grinvalds, Roberts | 6-3,6-4 |
| ITF Portugal F11 Qual | 2018/07/02 08:30 | Cortez, Afonso v Grinvalds, Roberts | 1-6,1-6 |
| ITF Portugal F11 Qual | 2018/06/30 08:30 | Sizya Ernest Kivanda v Grinvalds, Roberts | 2-6,6-7 |
| ITF Portugal F9 | 2018/06/18 09:00 | Cacao, Tiago v Grinvalds, Roberts | 6-1,6-3 |
| ITF Portugal F9 | 2018/06/17 11:30 | Ferreira, Goncalo v Grinvalds, Roberts | 6-3,1-6,2-6 |
| ITF Portugal F9 | 2018/06/16 09:00 | Ferreira, Joao (Por) v Grinvalds, Roberts | 1-6,6-7 |
| ITF Netherlands F1 Qual | 2018/06/24 09:00 | Dijkhuizen, Marc v Barretto, Paul | 3-6,2-6 |
| ITF Turkey F22 | 2018/06/05 09:20 | Dijkhuizen, Marc v Jonas Trinker | 1-6,3-6 |
| ITF Sweden F3 | 2018/05/21 08:00 | Dijkhuizen, Marc v Press, Frederik | 1-6,6-3,6-7 |
| ITF Sweden F3 Qual | 2018/05/20 09:00 | Dijkhuizen, Marc v Johnsson, Rasmus | 6-3,6-1 |
| ITF Sweden F2 | 2018/05/16 10:25 | Dijkhuizen, Marc v Petit, Gabriel | 3-6,6-4,3-6 |
| ITF Sweden F2 | 2018/05/15 08:30 | Dijkhuizen, Marc v Antoine Walch | 6-1,6-2 |
| Turkey F17, Singles Qualifying | 2018/05/01 13:30 | Robin Thour v Dijkhuizen, Marc | 6-4,7-5 |
| Turkey F16, Singles Qualifying | 2018/04/21 09:30 | Dijkhuizen, Marc v Lazar Vojinovic | 6-7,1-6 |