Stadium: Court 6 Round: 25 Ground: Clay
| ATP - Estoril - Herredouble | 2021/04/30 11:00 | Nys/Puetz v Klaasen/Mclachlan | 3-6,6-4,14-12 |
| ATP - Estoril - Herredouble | 2021/04/29 10:30 | Monroe/Tiafoe v Klaasen/Mclachlan | 3-6,7-6,6-10 |
| ATP - Estoril - Herredouble | 2021/04/28 11:00 | Bolelli/Gonzalez v Klaasen/Mclachlan | 2-6,3-6 |
| ATP - Beograd - Herredouble | 2021/04/20 15:25 | Sabanov/Sabanov v Klaasen/Mclachlan | 6-4,6-2 |
| ATP - Monte Carlo - Herredouble | 2021/04/16 15:15 | Evans/Skupski v Klaasen/Mclachlan | 1-6,7-6,10-4 |
| ATP - Monte Carlo - Herredouble | 2021/04/14 15:15 | Klaasen/Mclachlan v Ram/Salisbury | 6-7,6-3,10-5 |
| ATP - Monte Carlo - Herredouble | 2021/04/13 11:00 | De Minaur/Peers v Klaasen/Mclachlan | 6-7,6-3,9-11 |
| ATP - Miami - Herredouble | 2021/03/27 19:45 | Klaasen/Mclachlan v Demoliner/Gonzalez | 3-6,4-6 |