Stadium: Court 2 Round: 28 Ground: Hardcourt indoor
| Challenger St. Petersburg MD | 2021/03/04 09:30 | Hassan/Vatutin v Kadhe/Lock | 7-5,7-5 |
| Challenger St. Petersburg MD | 2021/03/03 13:45 | Golubev/Tiurnev v Hassan/Vatutin | 6-7,3-6 |
| Challenger St. Petersburg MD | 2021/03/04 11:10 | Bourchier/Vervoort v Eubanks/Quiroz | 7-6,2-6,8-10 |
| Challenger St. Petersburg MD | 2021/03/02 14:35 | Abazov/Vasilenko v Eubanks/Quiroz | 6-4,1-6,5-10 |