Stadium: Court 1 Round: 27 Ground: Clay
| WTA St. Petersburg WD | 2021/03/20 15:15 | Kalashnikova O / Kudryavtseva A v Christian K / Santamaria S | 7-5,4-6,4-10 |
| WTA - Saint-Malo - Doubles Femmes | 2021/05/04 17:15 | Kalashnikova O / Kudryavtseva A v Bolsova/Webley-Smith | 6-7,6-2,10-8 |
| WTA - Madrid - Doubles Femmes | 2021/04/30 09:00 | Dabrowski/Schuurs v Kalashnikova O / Kudryavtseva A | 7-6,7-5 |
| WTA - Stuttgart - Doubles Femmes | 2021/04/22 14:55 | Barthel / Friedsam v Kalashnikova O / Kudryavtseva A | 7-5,6-0 |
| WTA - Charleston - Doubles Femmes | 2021/04/12 18:00 | Kalashnikova O / Kudryavtseva A v Piter/Wang | 6-7,6-2,2-10 |
| WTA - Charleston - Doubles Femmes | 2021/04/05 18:25 | Jabeur/Potapova v Kalashnikova O / Kudryavtseva A | 6-1,6-4 |
| WTA St. Petersburg WD | 2021/03/20 15:15 | Kalashnikova O / Kudryavtseva A v Christian K / Santamaria S | 7-5,4-6,4-10 |
| WTA St. Petersburg WD | 2021/03/18 16:30 | Kalashnikova O / Kudryavtseva A v Marozava L / Sasnovich A | 4-6,7-5,16-14 |
| WTA St. Petersburg WD | 2021/03/17 13:05 | Kalashnikova O / Kudryavtseva A v Paar / Wachaczyk | 6-2,6-4 |
| WTA - Madrid - Doubles Femmes | 2021/04/29 13:45 | Perez/Zheng v Christian K / Santamaria S | 6-2,2-6,10-7 |
| WTA - Stuttgart - Doubles Femmes | 2021/04/19 13:00 | Barty/Brady v Christian K / Santamaria S | 6-3,6-1 |
| WTA - Charleston - Doubles Femmes | 2021/04/13 21:05 | Gumulya B / Rompies J v Christian K / Santamaria S | 7-6,3-6,12-10 |
| WTA St. Petersburg WD | 2021/03/21 10:30 | Kichenok N / Olaru R v Christian K / Santamaria S | 2-6,6-3,10-8 |
| WTA St. Petersburg WD | 2021/03/20 15:15 | Kalashnikova O / Kudryavtseva A v Christian K / Santamaria S | 7-5,4-6,4-10 |
| WTA St. Petersburg WD | 2021/03/18 12:20 | Vesnina/Zvonareva v Christian K / Santamaria S | 7-5,3-6,9-11 |
| WTA St. Petersburg WD | 2021/03/17 11:15 | Gorgodze/Rakhimova v Christian K / Santamaria S | 6-4,5-7,7-10 |
| WTA - Dubaï - Doubles Femmes | 2021/03/07 12:30 | Bertens/Kerkhove v Christian K / Santamaria S | 6-4,5-7,10-5 |