| Date | 30 July 2021 | |
|---|---|---|
| Location | Ariake Tennis Forest Park, Ariake, Koto, Tokyo, Japan | |
| Chair Umpire | Damien Dumusois |  FRA | 
| Seed | Competitor | NOC | Sets Won | Set 1 | Set 2 | Set 3 | |
|---|---|---|---|---|---|---|---|
| – | Nikola Mektić / Mate Pavić |  CRO | 2 | 6 | 3 | 10 | |
| – | Marin Čilić / Ivan Dodig |  CRO | 1 | 4 | 6 | 6 | 
 Nikola Mektić / Mate Pavić
Nikola Mektić / Mate Pavić| Pos | Seed | Competitor | |||
|---|---|---|---|---|---|
| – | Nikola Mektić | ||||
| – | Mate Pavić | ||||
| Team Totals | |||||
 Marin Čilić / Ivan Dodig
Marin Čilić / Ivan Dodig| Pos | Seed | Competitor | |||
|---|---|---|---|---|---|
| – | Marin Čilić | ||||
| – | Ivan Dodig | ||||
| Team Totals | |||||