| Swiss Open WD Qual | 2018/08/28 09:56 | Eric Jr Timmerrman v Hannes Gerberich | L | 0-2 |
| Dutch Open | 2018/10/10 11:15 | Joonas Korhonen v Lucas Corvee | L | 0-2 |
| Dutch Open | 2018/10/09 16:00 | Birger Abts v Joonas Korhonen | W | 1-2 |
| Swiss Open WD Qual | 2018/10/09 09:54 | Michael Spencer-Smith v Joonas Korhonen | W | 0-2 |
| Polish Int. | 2018/09/21 08:10 | Wei Chi Liu v Joonas Korhonen | L | 2-1 |
| Giraldilla Int. XD | 2018/04/13 13:20 | Joonas Korhonen v Toby Penty | L | 0-2 |
| Swiss Open WD Qual | 2018/04/12 14:55 | Karl Thor S'gaard v Joonas Korhonen | W | 0-2 |
| Swiss Open WD Qual | 2018/03/08 14:00 | Valentin Singer v Joonas Korhonen | W | 1-2 |
| Swiss Open WD Qual | 2018/03/08 10:30 | Joonas Korhonen v Douglas Lidman | W | 2-0 |