2021 National Bank Open – Men's doubles
# 2021 National Bank Open – Men's doubles

Marcel Granollers and Horacio Zeballos were the defending champions from when the tournament was last held in 2019, but withdrew before the tournament began.

Rajeev Ram and Joe Salisbury won the title, defeating Nikola Mektić and Mate Pavić in the final, 6–3, 4–6, [10–3]. By reaching the finals, the Croatian tandem became the second team since the Bryans in 2014, to reach 5 consecutive Masters 1000 finals.

## Seeds

The top four seeds receive a bye into the second round.

* Nikola Mektić / Mate Pavić (final)
* Juan Sebastián Cabal / Robert Farah (quarterfinals)
* Rajeev Ram / Joe Salisbury (champions)
* Kevin Krawietz / Horia Tecău (semifinals)
* Łukasz Kubot / Marcelo Melo (second round)
* John Peers / Filip Polášek (first round)
* Tim Pütz / Michael Venus (first round)
* Rohan Bopanna / Ivan Dodig (quarterfinals)

## Draw

### Key

* Q = Qualifier
* WC = Wild card
* LL = Lucky loser
* Alt = Alternate
* SE = Special exempt
* PR = Protected ranking
* ITF = ITF entry
* JE = Junior exempt
* w/o = Walkover
* r = Retired
* d = Defaulted
* SR = Special ranking

### Finals

| Semifinals | Semifinals | Semifinals | Semifinals | Final | Final | Final | Final | Final |
| - | - | - | - | - | - | - | - | - |
| 1 | Nikola Mektić Mate Pavić | $7^7$ | $7^{14}$ | | | | | |
| 4 | Kevin Krawietz Horia Tecău | $6^3$ | $6^{12}$ | | | | | |
| 4 | Kevin Krawietz Horia Tecău | $6^3$ | $6^{12}$ | 1 | Nikola Mektić Mate Pavić | 3 | 6 | [3] |
| | | | | 3 | Rajeev Ram Joe Salisbury | 6 | 4 | [10] |
| 3 | Rajeev Ram Joe Salisbury | 6 | 7 | 3 | Rajeev Ram Joe Salisbury | 6 | 4 | [10] |
| | Sander Gillé Joran Vliegen | 3 | 5 | | | | | |

### Top half

| First round | First round | First round | First round | First round | Second round | Second round | Second round | Second round | Second round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Semifinals | Semifinals | Semifinals | Semifinals |
| - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
| | | | | | 1 | N Mektić M Pavić | 3 | 7 | [13] | | | | | | | | | |
| Alt | M Kecmanović C Ruud | 5 | 3 | | | D Evans N Skupski | 6 | 5 | [11] | | | | | | | | | |
| | D Evans N Skupski | 7 | 6 | | | | | | | 1 | N Mektić M Pavić | 6 | $6^6$ | [10] | | | | |
| | J Murray M Purcell | $7^7$ | 1 | [11] | | | | | | | M Middelkoop L Saville | 3 | $7^8$ | [7] | | | | |
| | M Middelkoop L Saville | $6^5$ | 6 | [13] | | M Middelkoop L Saville | 6 | 1 | | | | | | | | | | |
| | A Bublik C Garín | 6 | 6 | | | A Bublik C Garín | 3 | $0^r$ | | | | | | | | | | |
| 6 | J Peers F Polášek | 4 | 4 | | | | | | | | | | | | 1 | N Mektić M Pavić | $7^7$ | $7^{14}$ |
| | | | | | | | | | | | | | | | 4 | K Krawietz H Tecău | $6^3$ | $6^{12}$ |
| | | | | | 4 | K Krawietz H Tecău | 6 | 1 | [12] | | | | | | | | | |
| | A Behar G Escobar | 7 | 3 | [11] | | O Marach P Oswald | 2 | 6 | [10] | | | | | | | | | |
| | O Marach P Oswald | 5 | 6 | [13] | | | | | | 4 | K Krawietz H Tecău | 6 | 3 | [10] | | | | |
| | A de Minaur C Norrie | 4 | $7^7$ | [8] | | | | | | | A Karatsev D Lajović | 3 | 6 | [3] | | | | |
| | A Karatsev D Lajović | 6 | $6^4$ | [10] | | A Karatsev D Lajović | 6 | 6 | | | | | | | | | | |
| | H Hurkacz J Sinner | 5 | 4 | | 5 | Ł Kubot M Melo | 4 | 4 | | | | | | | | | | |
| 5 | Ł Kubot M Melo | 7 | 6 | | | | | | | | | | | | | | | |

### Bottom half

| First round | First round | First round | First round | First round | Second round | Second round | Second round | Second round | Second round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Semifinals | Semifinals | Semifinals | Semifinals |
| - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
| 8 | R Bopanna I Dodig | 6 | $7^7$ | | | | | | | | | | | | | | | |
| | F Fognini L Sonego | 4 | $6^4$ | | 8 | R Bopanna I Dodig | 6 | 6 | | | | | | | | | | |
| WC | P Polansky B Schnur | 4 | 1 | | | S Bolelli M González | 4 | 3 | | | | | | | | | | |
| | S Bolelli M González | 6 | 6 | | | | | | | 8 | R Bopanna I Dodig | 6 | 3 | [4] | | | | |
| | M Čilić J-L Struff | 4 | 7 | [11] | | | | | | 3 | R Ram J Salisbury | 4 | 6 | [10] | | | | |
| | A Golubev A Mies | 6 | 5 | [13] | | A Golubev A Mies | 3 | 2 | | | | | | | | | | |
| | | | | | 3 | R Ram J Salisbury | 6 | 6 | | | | | | | | | | |
| | | | | | | | | | | | | | | | 3 | R Ram J Salisbury | 6 | 7 |
| 7 | T Pütz M Venus | 5 | $6^3$ | | | | | | | | | | | | | S Gillé J Vliegen | 3 | 5 |
| | S Gillé J Vliegen | 7 | $7^7$ | | | S Gillé J Vliegen | $7^7$ | 2 | [10] | | | | | | | | | |
| | R Klaasen B McLachlan | 4 | $6^4$ | | | W Koolhof A Krajicek | $6^5$ | 6 | [8] | | | | | | | | | |
| | W Koolhof A Krajicek | 6 | $7^7$ | | | | | | | | S Gillé J Vliegen | $6^5$ | 6 | [10] | | | | |
| | K Khachanov A Rublev | 6 | $7^8$ | | | | | | | 2 | JS Cabal R Farah | $7^7$ | 2 | [8] | | | | |
| WC | F Auger-Aliassime A Galarneau | 4 | $6^6$ | | | K Khachanov A Rublev | 3 | 4 | | | | | | | | | | |
| | | | | | 2 | JS Cabal R Farah | 6 | 6 | | | | | | | | | | |
