Round: 27 Ground: Hardcourt indoor
| Challenger Seville MD | 2015/09/10 16:35 | Koolhof/Middelkoop v Cachin/Munar | 7-6,6-3 |
| Challenger Meerbusch MD | 2015/08/23 11:00 | Koolhof/Middelkoop v Brown/Junaid | 4-6,5-7 |
| Challenger Meerbusch MD | 2015/08/20 12:00 | Kretschmer/Satschko v Koolhof/Middelkoop | 4-6,6-3,2-10 |
| Challenger St Brieuc MD | 2015/04/09 17:35 | Koolhof/Middelkoop v Cagnina/Gigounon | 6-1,4-6,9-11 |
| Challenger Guangzhou MD | 2015/03/11 05:55 | Kretschmer/Satschko v Koolhof/Middelkoop | 6-7,6-7 |
| ITF France F3 MD | 2015/01/29 16:00 | Koolhof/Middelkoop v Authom/Mertens | 6-3,6-4 |
| Challenger Casablanca MD | 2015/01/14 15:05 | Koolhof/Middelkoop v Mektic/Skugor | 7-6,6-4 |