# 2021 Cassis Open Provence – Singles

Jo-Wilfried Tsonga was the defending champion but chose not to defend his title.
Benjamin Bonzi won the title after defeating Lucas Pouille 7–6$^{(7–4)}$, 6–4 in the final.

## Seeds

* Benjamin Bonzi (champion)
* Yasutaka Uchiyama (withdrew)
* Christopher O'Connell (withdrew)
* Mikhail Kukushkin (first round, retired)
* Lucas Pouille (final)
* Grégoire Barrère (first round)
* Jurij Rodionov (first round)
* Liam Broady (semifinals)

## 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 |
| 1 | Benjamin Bonzi | 6 | 6 | | | | |
| | Kacper Żuk | 3 | 4 | | | | |
| | Kacper Żuk | 3 | 4 | 1 | Benjamin Bonzi | 7$^7$ | 6 |
| | | | | 5 | Lucas Pouille | 6$^4$ | 4 |
| 8 | Liam Broady | 4 | 3 | 5 | Lucas Pouille | 6$^4$ | 4 |
| 5 | Lucas Pouille | 6 | 6 | | | | |

### 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 | B Bonzi | 7 | 6 | | | | | | | | | | | | | | | |
| | T Fabbiano | 5 | 3 | | 1 | B Bonzi | 7 | 7$^7$ | | | | | | | | | | |
| LL | A Galarneau | 6 | 6 | | LL | A Galarneau | 5 | 6$^4$ | | | | | | | | | | |
| Alt | B Tomic | 1 | 2 | | | | | | | 1 | B Bonzi | 6 | 3 | 6 | | | | |
| WC | L Van Assche | 5 | | | | | | | | WC | L Van Assche | 3 | 6 | 2 | | | | |
| Alt | Yo Watanuki | 0$^r$ | | | WC | L Van Assche | 6 | 6$^0$ | 6 | | | | | | | | | |
| | A Çelikbilek | 6 | 6 | | | A Çelikbilek | 3 | 7$^7$ | 3 | | | | | | | | | |
| 6 | G Barrère | 3 | 3 | | | | | | | | | | | | 1 | B Bonzi | 6 | 6 |
| 4 | M Kukushkin | 0 | 2$^r$ | | | | | | | | | | | | | K Żuk | 3 | 4 |
| | R Safiullin | 6 | 4 | | | R Safiullin | 6$^{10}$ | 6 | 2 | | | | | | | | | |
| Q | G Mpetshi Perricard | 2 | 4 | | | T Kokkinakis | 7$^{12}$ | 3 | 6 | | | | | | | | | |
| | T Kokkinakis | 6 | 6 | | | | | | | | T Kokkinakis | 4 | 6$^3$ | | | | | |
| WC | A Fils | 6$^{13}$ | 7 | 1 | | | | | | | K Żuk | 6 | 7$^7$ | | | | | |
| Alt | T Ito | 7$^{15}$ | 5 | 6 | Alt | T Ito | 5 | 3 | | | | | | | | | | |
| | K Żuk | 6 | 6 | | | K Żuk | 7 | 6 | | | | | | | | | | |
| 7 | J Rodionov | 3 | 3 | | | | | | | | | | | | | | | |

### 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 | Semifinals | Semifinals | Semifinals | Semifinals |
| 8 | L Broady | 6 | 6 | | | | | | | | | | | | | | |
| | E Escobedo | 2 | 4 | | 8 | L Broady | 7$^7$ | 7$^7$ | | | | | | | | | |
| LL | L Lokoli | 2 | 2 | | | M Bourgue | 6$^3$ | 6$^0$ | | | | | | | | | |
| | M Bourgue | 6 | 6 | | | | | | | 8 | L Broady | 7$^9$ | 6 | | | | |
| Alt | H Grenier | 6 | 6$^{11}$ | 6 | | | | | | Q | R Ramanathan | 6$^7$ | 4 | | | | |
| | G Soeda | 4 | 7$^{13}$ | 1 | Alt | H Grenier | 6 | 3 | 4 | | | | | | | | |
| | E Gulbis | 3 | 6 | 2 | Q | R Ramanathan | 4 | 6 | 6 | | | | | | | | |
| Q | R Ramanathan | 6 | 0 | 6 | | | | | | | | | | 8 | L Broady | 4 | 3 |
| 5 | L Pouille | 6 | 7$^7$ | | | | | | | | | | | 5 | L Pouille | 6 | 6 |
| | J Sousa | 1 | 6$^3$ | | 5 | L Pouille | 7$^7$ | 6 | | | | | | | | | |
| | E Ymer | 7 | 6 | | | E Ymer | 6$^5$ | 1 | | | | | | | | | |
| | A Müller | 5 | 4 | | | | | | | 5 | L Pouille | 7$^7$ | 6 | | | | |
| Q | H Moriya | 6 | 7$^7$ | | | | | | | WC | C Chidekh | 6$^1$ | 4 | | | | |
| Q | N Jarry | 4 | 6$^5$ | | Q | H Moriya | 3 | 0 | | | | | | | | | |
| WC | C Chidekh | 6 | 6 | | WC | C Chidekh | 6 | 6 | | | | | | | | | |
| LL | A Cazaux | 4 | 4 | | | | | | | | | | | | | | |