# 2021 Citi Open – Singles

Jannik Sinner defeated Mackenzie McDonald in the final, 7–5, 4–6, 7–5 to win the singles tennis title at the 2021 Citi Open. With the victory, Sinner became the youngest player and first teenager on the ATP Tour to win an ATP 500 title since the category was created in 2009.
Nick Kyrgios was the reigning champion from when the tournament was last held in 2019, but lost in the first round to McDonald.

## Seeds

All seeds receive a bye into the second round.
    01. Rafael Nadal (third round)
    02. Félix Auger-Aliassime (third round)
    03. Alex de Minaur (second round)
    04. Grigor Dimitrov (second round)
    05. Jannik Sinner (champion)
    06. Dan Evans (second round)
    07. Cameron Norrie (third round)
    08. Reilly Opelka (third round)
    09. Alexander Bublik (second round)
    10. Taylor Fritz (second round)
    11. John Millman (quarterfinals)
    12. Sebastian Korda (third round)
    13. Benoît Paire (second round)
    14. Lloyd Harris (quarterfinals)
    15. Miomir Kecmanović (second round)
    16. Frances Tiafoe (second round)
Click on the seed number of a player to go to their draw section.

## 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

| Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Semifinals | Semifinals | Semifinals | Semifinals | Semifinals | Final | Final | Final | Final | Final |
| 14 | Lloyd Harris | 3 | 5 | | | | | | | | | | |
| | Kei Nishikori | 6 | 7 | | | | | | | | | | |
| | Kei Nishikori | 6 | 7 | | Kei Nishikori | 4 | 6 | 5 | | | | | |
| | | | | | Mackenzie McDonald | 6 | 3 | 7 | | | | | |
| | Mackenzie McDonald | 6 | 6 | | Mackenzie McDonald | 6 | 3 | 7 | | | | | |
| | Denis Kudla | 3 | 2 | | | | | | | | | | |
| | Denis Kudla | 3 | 2 | | | | | | | Mackenzie McDonald | 5 | 6 | 5 |
| | | | | | | | | | 5 | Jannik Sinner | 7 | 4 | 7 |
| 5 | Jannik Sinner | 6 | 6 | | | | | | | | | | | 5 | Jannik Sinner | 7 | 4 | 7 |
| | Steve Johnson | 4 | 2 | | | | | | | | | | |
| | Steve Johnson | 4 | 2 | 5 | Jannik Sinner | 7$^7$ | 6 | | | | | | |
| | | | | WC | Jenson Brooksby | 6$^2$ | 1 | | | | | | |
| 11 | John Millman | 1 | 2 | WC | Jenson Brooksby | 6$^2$ | 1 | | | | | | |
| WC | Jenson Brooksby | 6 | 6 | | | | | | | | | | |

### Top half
#### Section 1

| First round | First round | First round | First round | First round | Second round | Second round | Second round | Second round | Second round | Third round | Third round | Third round | Third round | Third round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals |
| | | | | | 1/WC | R Nadal | 6 | 4 | 7$^7$ | | | | | | | | | |
| WC | J Sock | 6$^3$ | 4 | | WC | J Sock | 2 | 6 | 6$^1$ | | | | | | | | | |
| | Y Nishioka | 7$^7$ | 0$^r$ | | | | | | | 1/WC | R Nadal | 4 | 6 | 4 | | | | |
| | T Sandgren | 6 | 2 | 6 | | | | | | 14 | L Harris | 6 | 1 | 6 | | | | |
| | J Duckworth | 3 | 6 | 2 | | T Sandgren | 4 | 0$^r$ | | | | | | | | | | |
| | | | | | 14 | L Harris | 6 | 1 | | | | | | | | | | |
| | | | | | | | | | | | | | | | 14 | L Harris | 3 | 5 |
| | | | | | | | | | | | | | | | | K Nishikori | 6 | 7 |
| | | | | | 9 | A Bublik | 2 | 5 | | | | | | | | | | |
| | K Nishikori | 6 | 6 | | | K Nishikori | 6 | 7 | | | | | | | | | | |
| | S Querrey | 4 | 3 | | | | | | | | K Nishikori | 3 | 6 | 6 | | | | |
| | M Giron | 4 | 6 | 7$^7$ | | | | | | 7 | C Norrie | 6 | 3 | 3 | | | | |
| Q | I Marchenko | 6 | 4 | 6$^1$ | | M Giron | 4 | 3 | | | | | | | | | | |
| | | | | | 7 | C Norrie | 6 | 6 | | | | | | | | | | |

#### Section 2

| First round | First round | First round | First round | First round | Second round | Second round | Second round | Second round | Second round | Third round | Third round | Third round | Third round | Third round | Quarterfinals | Quarterfinals | Quarterfinals |
| | | | | | 4 | G Dimitrov | 2 | 6$^4$ | | | | | | | | | |
| | E Gerasimov | 5 | 4 | | | I Ivashka | 6 | 7$^7$ | | | | | | | | | |
| | I Ivashka | 7 | 6 | | | | | | | | I Ivashka | 4 | 4 | | | | |
| | M McDonald | 6 | 6 | | | | | | | | M McDonald | 6 | 6 | | | | |
| | N Kyrgios | 4 | 4 | | | M McDonald | 6$^6$ | 6 | 6 | | | | | | | | |
| | | | | | 13 | B Paire | 7$^8$ | 4 | 4 | | | | | | | | |
| | | | | | | | | | | | | | | | M McDonald | 6 | 6 |
| | | | | | | | | | | | | | | | D Kudla | 3 | 2 |
| | | | | | 10 | T Fritz | 4 | 2 | | | | | | | | | |
| | D Kudla | 6 | 6$^5$ | 6 | | D Kudla | 6 | 6 | | | | | | | | | |
| WC | F López | 3 | 7$^7$ | 3 | | | | | | | D Kudla | 3 | 7$^7$ | 6 | | | |
| WC | B Nakashima | 6 | 6 | | | | | | | WC | B Nakashima | 6 | 6$^3$ | 4 | | | |
| | A Popyrin | 3 | 3 | | WC | B Nakashima | 7$^7$ | 6 | | | | | | | | | |
| | | | | | 6 | D Evans | 6$^1$ | 0 | | | | | | | | | |

### Bottom half
#### Section 3

| First round | First round | First round | First round | First round | Second round | Second round | Second round | Second round | Second round | Third round | Third round | Third round | Third round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals |
| | | | | | 5 | J Sinner | 6 | 6 | | | | | | | | | |
| Q | P Gunneswaran | 6 | 1 | 1 | | E Ruusuvuori | 2 | 4 | | | | | | | | | |
| | E Ruusuvuori | 2 | 6 | 6 | | | | | | 5 | J Sinner | 7$^7$ | 7$^7$ | | | | |
| Q | E Gómez | 6 | 3 | 3 | | | | | | 12 | S Korda | 6$^3$ | 6$^3$ | | | | |
| | V Pospisil | 4 | 6 | 6 | | V Pospisil | 5 | 4 | | | | | | | | | |
| | | | | | 12 | S Korda | 7 | 6 | | | | | | | | | |
| | | | | | | | | | | | | | | 5 | J Sinner | 6 | 6 |
| | | | | | | | | | | | | | | | S Johnson | 4 | 2 |
| | | | | | 15 | M Kecmanović | 3 | 2 | | | | | | | | | |
| Q | M Krueger | 6$^4$ | 2 | | | R Berankis | 6 | 6 | | | | | | | | | |
| | R Berankis | 7$^7$ | 6 | | | | | | | | R Berankis | 2 | 1 | | | | |
| | S Johnson | 6 | 7$^7$ | | | | | | | | S Johnson | 6 | 6 | | | | |
| Q | R Ramanathan | 3 | 6$^0$ | | | S Johnson | 6$^5$ | 6 | 6 | | | | | | | | |
| | | | | | 3 | A de Minaur | 7$^7$ | 4 | 2 | | | | | | | | |

#### Section 4

| First round | First round | First round | First round | First round | Second round | Second round | Second round | Second round | Second round | Third round | Third round | Third round | Third round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals |
| | | | | | 8 | R Opelka | 7$^7$ | 6 | | | | | | | | | |
| | T Paul | 4 | 3 | | | DE Galán | 6$^1$ | 3 | | | | | | | | | |
| | DE Galán | 6 | 6 | | | | | | | 8 | R Opelka | 3 | 6$^4$ | | | | |
| Q | E Ymer | 3 | 7 | 6 | | | | | | 11 | J Millman | 6 | 7$^7$ | | | | |
| | J Thompson | 6 | 5 | 3 | Q | E Ymer | 2 | 6$^8$ | | | | | | | | | |
| | | | | | 11 | J Millman | 6 | 7$^{10}$ | | | | | | | | | |
| | | | | | | | | | | | | | | 11 | J Millman | 1 | 2 |
| | | | | | | | | | | | | | | WC | J Brooksby | 6 | 6 |
| | | | | | 16 | F Tiafoe | 6$^4$ | 5 | | | | | | | | | |
| | K Anderson | 6$^4$ | 3 | | WC | J Brooksby | 7$^7$ | 7 | | | | | | | | | |
| WC | J Brooksby | 7$^7$ | 6 | | | | | | | WC | J Brooksby | 6 | 6 | | | | |
| | Y Uchiyama | 6 | 5 | 3 | | | | | | 2 | F Auger-Aliassime | 3 | 4 | | | | |
| | A Seppi | 3 | 7 | 6 | | A Seppi | 6 | 2 | 2 | | | | | | | | |
| | | | | | 2 | F Auger-Aliassime | 2 | 6 | 6 | | | | | | | | |

## Qualifying
### Seeds

* Yasutaka Uchiyama (moved to the main draw)
* Liam Broady (qualifying competition)
* J. J. Wolf (qualifying competition)
* Maxime Cressy (qualifying competition)
* Evgeny Donskoy (first round)
* Prajnesh Gunneswaran (qualified)
* Illya Marchenko (qualified)
* Jason Jung (first round)
* Sebastian Ofner (qualifying competition)
* Emilio Gómez (qualified)
* Elias Ymer (qualified)
* Mitchell Krueger (qualified)

### Qualifiers

* Ramkumar Ramanathan
* Emilio Gómez
* Elias Ymer
* Illya Marchenko
* Mitchell Krueger
* Prajnesh Gunneswaran

### Qualifying draw
#### First qualifier

| First round | First round | First round | First round | First round | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition |
| Alt | Ramkumar Ramanathan | 6 | 3 | 6 | | | | |
| Alt | Christopher Eubanks | 4 | 6 | 3 | | | | |
| Alt | Christopher Eubanks | 4 | 6 | 3 | Alt | Ramkumar Ramanathan | 7 | 6 |
| | | | | | 9 | Sebastian Ofner | 5 | 1 |
| PR | Tatsuma Ito | 6$^4$ | 2 | | 9 | Sebastian Ofner | 5 | 1 |
| 9 | Sebastian Ofner | 7$^7$ | 6 | | | | | |

#### Second qualifier

| First round | First round | First round | First round | First round | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition |
| 2 | Liam Broady | 6 | 2 | 6 | | | | |
| Alt | Mikael Torpegaard | 4 | 6 | 3 | | | | |
| Alt | Mikael Torpegaard | 4 | 6 | 3 | 2 | Liam Broady | 4 | 6$^0$ |
| | | | | | 10 | Emilio Gómez | 6 | 7$^7$ |
| Alt | Matthew Ebden | 3 | 1 | | 10 | Emilio Gómez | 6 | 7$^7$ |
| 10 | Emilio Gómez | 6 | 6 | | | | | |

#### Third qualifier

| First round | First round | First round | First round | First round | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition |
| 3/PR | J. J. Wolf | 6$^5$ | 7$^7$ | 6 | | | | |
| WC | Ulises Blanch | 7$^7$ | 6$^3$ | 3 | | | | |
| WC | Ulises Blanch | 7$^7$ | 6$^3$ | 3 | 3/PR | J. J. Wolf | 6$^5$ | 6$^4$ |
| | | | | | 11 | Elias Ymer | 7$^7$ | 7$^7$ |
| | Bjorn Fratangelo | 4 | 3 | | 11 | Elias Ymer | 7$^7$ | 7$^7$ |
| 11 | Elias Ymer | 6 | 6 | | | | | |

#### Fourth qualifier

| First round | First round | First round | First round | First round | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition |
| 4 | Maxime Cressy | 6 | 7 | | | | | | |
| | Michael Mmoh | 2 | 5 | | | | | | |
| | Michael Mmoh | 2 | 5 | | 4 | Maxime Cressy | 5 | 7$^7$ | 3 |
| | | | | | 7 | Illya Marchenko | 7 | 6$^4$ | 6 |
| WC | Ivo Karlović | 3 | 7$^{12}$ | 3 | 7 | Illya Marchenko | 7 | 6$^4$ | 6 |
| 7 | Illya Marchenko | 6 | 6$^{10}$ | 6 | | | | | |

#### Fifth qualifier

| First round | First round | First round | First round | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition |
| 5 | Evgeny Donskoy | 6$^5$ | 4 | | | | | |
| Alt | Max Purcell | 7$^7$ | 6 | | | | | |
| Alt | Max Purcell | 7$^7$ | 6 | Alt | Max Purcell | 6 | 3 | 2 |
| | | | | 12 | Mitchell Krueger | 3 | 6 | 6 |
| WC | Andrew Fenty | 4 | 4 | 12 | Mitchell Krueger | 3 | 6 | 6 |
| 12 | Mitchell Krueger | 6 | 6 | | | | | |

#### Sixth qualifier

| First round | First round | First round | First round | First round | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition |
| 6 | Prajnesh Gunneswaran | 6 | 6 | | | | | |
| WC | Luke Saville | 2 | 2 | | | | | |
| WC | Luke Saville | 2 | 2 | | 6 | Prajnesh Gunneswaran | 6 | 6 |
| | | | | | | Go Soeda | 3 | 1 |
| | Go Soeda | 6 | 6$^2$ | 6 | | Go Soeda | 3 | 1 |
| 8 | Jason Jung | 4 | 7$^7$ | 4 | | | | |