 USA: Indian Wells - Doubles - Main |
|---|
| 1/8-finals | Mattek-Sands B./Swiatek I. | Hsieh S-W./Mertens E. | 1:2 (6:1, 4:6, 8:10) | details | 11.10.2021 |
| 1/16-finals | Mattek-Sands B./Swiatek I. | Lohoff J./Panova A. | 2:0 (6:1, 6:3) | details | 07.10.2021 |
| USA: Cincinnati - Doubles - Main |
|---|
| Quarter-finals | Mattek-Sands B./Swiatek I. | Krejcikova B./Siniakova K. | 0:2 (4:6, 3:6) | details | 20.08.2021 |
| 1/8-finals | Jurak Schreiber D./Klepac A. | Mattek-Sands B./Swiatek I. | 1:2 (6:4, 1:6, 3:10) | details | 19.08.2021 |
| 1/16-finals | Mattek-Sands B./Swiatek I. | Martic P./Rogers S. | 2:1 (2:6, 7:5, 10:5) | details | 18.08.2021 |
 France: French Open - Doubles - Main |
|---|
| Final | Mattek-Sands B./Swiatek I. | Krejcikova B./Siniakova K. | 0:2 (4:6, 2:6) | details | 13.06.2021 |
| Semi-finals | Mattek-Sands B./Swiatek I. | Begu I./Podoroska N. | 2:0 (6:3, 6:4) | details | 11.06.2021 |
| Quarter-finals | Mattek-Sands B./Swiatek I. | Jurak Schreiber D./Klepac A. | 2:0 (6:3, 6:2) | details | 08.06.2021 |
| 1/8-finals | Hsieh S-W./Mertens E. | Mattek-Sands B./Swiatek I. | 1:2 (7:5, 4:6, 5:7) | details | 06.06.2021 |
| 1/16-finals | Friedsam A-L./Wang Y. | Mattek-Sands B./Swiatek I. | 0:2 (5:7, 3:6) | details | 04.06.2021 |
 Spain: Madrid - Doubles - Main |
|---|
| 1/8-finals | Vesnina E./Zvonareva V. | Mattek-Sands B./Swiatek I. | 2:1 (4:6, 6:3, 10:5) | details | 04.05.2021 |
| 1/16-finals | Mattek-Sands B./Swiatek I. | Carter H./Stefani L. | 2:1 (2:6, 6:3, 10:6) | details | 30.04.2021 |
| USA: Miami - Doubles - Main |
|---|
| Semi-finals | Mattek-Sands B./Swiatek I. | Aoyama S./Shibahara E. | 1:2 (6:3, 64:7, 2:10) | details | 02.04.2021 |
| Quarter-finals | Kichenok L./Ostapenko J. | Mattek-Sands B./Swiatek I. | 0:2 (1:6, 4:6) | details | 31.03.2021 |
| 1/8-finals | Mattek-Sands B./Swiatek I. | Xu Y./Zhang S. | 2:0 (6:3, 6:1) | details | 28.03.2021 |
| 1/16-finals | Blinkova A./Niculescu M. | Mattek-Sands B./Swiatek I. | 0:2 (0:6, 1:6) | details | 26.03.2021 |
