Stadium: Centre Court Darmstadt Round: 28
| ITF Women Oeiras | 2018/05/24 17:00 | Lucia Martinez v Romy Koelzer | 7-5,3-6,6-3 |
| ITF Women Oeiras | 2018/05/23 11:15 | Kamilla Kokeladze v Romy Koelzer | 2-6,4-6 |
| ITF Women Wiesbaden | 2018/04/26 09:00 | Romy Koelzer v Kimberley Zimmermann | 3-6,1-6 |
| ITF Women Wiesbaden | 2018/04/25 09:00 | Anna Bondar v Romy Koelzer | 6-2,3-6,6-7 |
| ITF Women Wiesbaden Qual | 2018/04/24 08:00 | Romy Koelzer v Luna Meers | 4-6,6-0,6-1 |
| ITF Women Wiesbaden Qual | 2018/04/23 10:30 | Romy Koelzer v Stephanie Bertschmann | 6-0,6-3 |
| ITF Women Obidos | 2018/04/18 09:30 | Ganna Poznikhirenko v Romy Koelzer | 6-2,6-0 |
| ITF Women Obidos Qual | 2018/04/17 12:45 | Aleksandrina Naydenova v Romy Koelzer | 0-6,7-6,4-6 |
| WTA Nurnberg Qual | 2018/05/19 13:05 | Katharina Gerlach v Anna Zaja | 6-7,3-6 |
| ITF Women Balatonboglar | 2018/05/02 10:55 | Kaja Juvan v Katharina Gerlach | 6-2,6-1 |
| ITF Women Balatonboglar | 2018/05/01 09:40 | Katharina Gerlach v Dalma Galfi | 6-3,4-6,6-2 |
| WTA Stuttgart Qual | 2018/04/21 11:45 | Su-Wei Hsieh v Katharina Gerlach | 2-6,7-5,6-2 |
| ITF Women Santa Margherita Qual | 2018/03/27 13:00 | Martina Di Giuseppe v Katharina Gerlach | 6-3,7-5 |
| ITF Women Santa Margherita Qual | 2018/03/21 10:30 | Tena Lukas v Katharina Gerlach | 6-4,6-2 |
| ITF Women Santa Margherita Qual | 2018/03/19 13:00 | Ana Vrljic v Katharina Gerlach | 4-6,3-6 |
| ITF Women Santa Margherita Qual | 2018/03/13 13:00 | Manon Arcangioli v Katharina Gerlach | 6-3,6-3 |