stadio: Court 1 Round: 27 Ground: Clay
| ATP Budapest DM | 2018/04/25 09:00 | Mektic/Peya v Koolhof/Sitak | 5-7,7-6,7-10 |
| ATP Marrakech DM | 2018/04/11 16:50 | Koolhof/Sitak v Sharan/Struff | 6-7,3-6 |
| Challenger Alicante DM | 2018/04/06 14:45 | Koolhof/Sitak v Andreozzi/Behar | 6-3,6-2 |
| Challenger Alicante DM | 2018/04/05 09:30 | Koolhof/Sitak v Martinez Portero/Vega Hernandez | 5-7,6-4,10-5 |
| Challenger Alicante DM | 2018/04/02 12:35 | Koolhof/Sitak v Cervantes/Marrero | 6-4,6-1 |
| Challenger Irving DM | 2018/03/16 23:10 | Petzschner/Peya v Koolhof/Sitak | 6-4,7-5 |
| Challenger Irving DM | 2018/03/15 22:25 | Koolhof/Sitak v Krajicek/Lacko | 6-1,6-4 |
| Challenger Irving DM | 2018/03/14 19:00 | Inglot/Skupski v Koolhof/Sitak | 6-3,1-6,6-10 |
| ATP Budapest DM | 2018/04/25 11:10 | Sharan/Skupski v Matkowski/Monroe | 2-6,3-6 |