Stadium: COURT 1 Round: 26 Ground: Hardcourt indoor
| ATP Sofia MD | 2021/10/01 09:00 | Gonzalez/Molteni v Brkic/Cacic | 6-7,6-2,10-4 |
| ATP Moscow MD | 2021/10/24 11:40 | Brkic/Cacic v Heliovaara/Middelkoop | 5-7,6-4,9-11 |
| ATP Moscow MD | 2021/10/22 15:05 | Ivashka/Martinez v Brkic/Cacic | 4-6,6-4,8-10 |
| ATP Moscow MD | 2021/10/21 11:00 | Brkic/Cacic v Inglot/Skupski | 7-6,5-7,10-8 |
| ATP Moscow MD | 2021/10/18 11:00 | Brkic/Cacic v Bublik/Mannarino | 6-2,6-1 |
| ATP Sofia MD | 2021/10/01 09:00 | Gonzalez/Molteni v Brkic/Cacic | 6-7,6-2,10-4 |
| ATP Sofia MD | 2021/09/29 10:40 | Golubev/Nedovyesov v Brkic/Cacic | 3-6,7-6,7-10 |
| ATP Metz MD | 2021/09/24 13:35 | Nys/Rinderknech v Brkic/Cacic | 6-3,7-6 |
| ATP Metz MD | 2021/09/23 14:10 | Reese/Verbeek v Brkic/Cacic | 3-6,3-6 |
| ATP Moscow MD | 2021/10/22 10:10 | Behar/Escobar v Gonzalez/Molteni | 7-5,3-6,10-7 |
| ATP Moscow MD | 2021/10/20 08:00 | Gonzalez/Molteni v Golubev/Nys | 7-5,6-7,10-7 |
| ATP Sofia MD | 2021/10/02 10:05 | Marach/Oswald v Gonzalez/Molteni | 2-6,7-5,10-6 |
| ATP Sofia MD | 2021/10/01 09:00 | Gonzalez/Molteni v Brkic/Cacic | 6-7,6-2,10-4 |
| ATP Sofia MD | 2021/09/30 11:50 | Gonzalez/Molteni v Milushev/Shandarov | 6-3,6-4 |
| ATP Nur-Sultan MD | 2021/09/26 06:00 | Gonzalez/Molteni v Erlich/Vasilevski | 6-1,6-2 |
| ATP Nur-Sultan MD | 2021/09/25 06:00 | Gonzalez/Molteni v Berankis/Sitak | 6-4,6-0 |
| ATP Nur-Sultan MD | 2021/09/24 06:00 | Gonzalez/Molteni v Glasspool/Heliovaara | 5-7,6-4,10-8 |