| Denmark Masters MD | 2021/08/06 11:00 | Sondergaard/Toft v Corvee/Labar | L | 1-2 |
| Austrian Open - Doubles Hommes | 2021/05/29 11:10 | Chang/Chia v Sondergaard/Toft | L | 2-1 |
| Austrian Open - Doubles Hommes | 2021/05/28 15:40 | Sondergaard/Toft v Janacek J / Svejda T | W | 2-0 |
| Slovenia Int. MD | 2021/05/20 17:20 | Sondergaard/Toft v Arif/Haikal | L | 0-2 |
| Portuguese Int. MD | 2021/05/08 11:20 | Lauritzen/Vestergaard v Sondergaard/Toft | L | 2-1 |
| Orleans Masters MD | 2021/03/24 17:10 | Sondergaard/Toft v Kræmer/Rindshøj | L | 1-2 |
| SaarLorLux Open 2019, MD | 2020/10/30 13:10 | Sondergaard/Toft v Jansen J R / Kaesbauer P | L | 1-2 |
| SaarLorLux Open 2019, MD | 2020/10/29 12:00 | Hess D / Pistorius J v Sondergaard/Toft | W | 0-2 |
| Spain Int XD | 2021/06/18 13:45 | Kargaev R / Vorobeva V v Duijs G / van Der Aar W | L | 2-1 |
| Spain Int XD | 2021/06/18 07:00 | Mini/Saponara Rivva v Duijs G / van Der Aar W | W | 1-2 |
| Spain Int XD | 2021/06/17 11:00 | Perez/Leal v Duijs G / van Der Aar W | W | 1-2 |
| Portuguese Int. XD | 2021/05/07 13:50 | Kraemer K H / Kudsk A C v Duijs G / van Der Aar W | L | 2-1 |
| Open de Pologne - Doubles Hommes | 2021/03/27 09:00 | Duijs G / van Der Aar W v Man/Tee | L | 0-2 |
| Open de Pologne - Doubles Hommes | 2021/03/26 18:50 | Duijs G / van Der Aar W v Kona / Sharma | W | 2-0 |
| Open de Pologne - Doubles Hommes | 2021/03/26 18:50 | Duijs G / van Der Aar W v Kona / Sharma | W | 2-0 |
| Open de Pologne - Doubles Hommes | 2021/03/26 12:40 | Yann Orteu/Pham v Duijs G / van Der Aar W | W | 1-2 |