# 2021 President's Cup II – Singles

Max Purcell was the defending champion but chose not to defend his title.
Andrey Kuznetsov won the title after Jason Kubler retired trailing 3–6, 1–2 in the final.

## Seeds

* Roman Safiullin (withdrew)
* Sergiy Stakhovsky (second round)
* Jay Clarke (first round)
* Hugo Grenier (quarterfinals)
* Peter Polansky (quarterfinals)
* Jesper de Jong (second round)
* Tseng Chun-hsin (second round)
* Wu Tung-lin (first round)

## 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 | Semifinals | Final | Final | Final |
| | Pavel Kotov | 2 | 7$^7$ | 4 | | | |
| | Andrey Kuznetsov | 6 | 6$^4$ | 6 | | | |
| | Andrey Kuznetsov | 6 | 6$^4$ | 6 | Andrey Kuznetsov | 6 | 2 |
| | | | | | Jason Kubler | 3 | 1$^r$ |
| | Jason Kubler | 6 | 6 | | Jason Kubler | 3 | 1$^r$ |
| Q | Oleksii Krutykh | 1 | 3 | | | | |

### 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 |
| LL | E Kırkın | 2 | 3 | | | | | | | | | | | | | | | |
| | R Peniston | 6 | 6 | | | R Peniston | 6 | 6 | | | | | | | | | | |
| | A Bega | 3 | 6 | 3 | | Y-h Hsu | 3 | 4 | | | | | | | | | | |
| | Y-h Hsu | 6 | 1 | 6 | | | | | | | R Peniston | 4 | 2 | | | | | |
| | P Kotov | 3 | 6 | 6 | | | | | | | P Kotov | 6 | 6 | | | | | |
| Q | E Leshem | 6 | 1 | 4 | | P Kotov | 6 | 7$^7$ | | | | | | | | | | |
| | D Yevseyev | 6 | 0 | 3 | 6 | J de Jong | 3 | 6$^3$ | | | | | | | | | | |
| 6 | J de Jong | 4 | 6 | 6 | | | | | | | | | | | P Kotov | 2 | 7$^7$ | 4 |
| 3 | J Clarke | 6$^6$ | 4 | | | | | | | | | | | | A Kuznetsov | 6 | 6$^4$ | 6 |
| | A Kuznetsov | 7$^8$ | 6 | | | A Kuznetsov | 6 | 7 | | | | | | | | | | |
| WC | B Zhukayev | 6 | 6 | | WC | B Zhukayev | 2 | 5 | | | | | | | | | | |
| | L Catarina | 2 | 4 | | | | | | | | A Kuznetsov | 6 | 3 | 6 | | | | |
| | A Zakharov | 0 | 2 | | | | | | | 5 | P Polansky | 2 | 6 | 2 | | | | |
| | M Jaziri | 6 | 6 | | | M Jaziri | 6 | 5 | 6$^4$ | | | | | | | | | |
| Q | A Dubrivnyy | 5 | 6$^5$ | | 5 | P Polansky | 3 | 7 | 7$^7$ | | | | | | | | | |
| 5 | P Polansky | 7 | 7$^7$ | | | | | | | | | | | | | | | |

### 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 |
| 7 | C-h Tseng | 6 | 6 | | | | | | | | | | | | | | | |
| | C Denolly | 4 | 4 | | 7 | C-h Tseng | 6 | 3 | 5 | | | | | | | | | |
| | J Kubler | 6 | 7 | | | J Kubler | 0 | 6 | 7 | | | | | | | | | |
| | K Sultanov | 3 | 5 | | | | | | | | J Kubler | 7$^7$ | 6 | | | | | |
| WC | Dostanbek Tashbulatov | 3 | 2 | | | | | | | 4 | H Grenier | 6$^4$ | 1 | | | | | |
| | I Nedelko | 6 | 6 | | | I Nedelko | 5$^r$ | | | | | | | | | | | |
| | Y-s Chung | 7$^7$ | 3 | 1 | 4 | H Grenier | 6 | | | | | | | | | | | |
| 4 | H Grenier | 6$^5$ | 6 | 6 | | | | | | | | | | | | J Kubler | 6 | 6 |
| 8 | T-l Wu | 2 | 2 | | | | | | | | | | | | Q | O Krutykh | 1 | 3 |
| Q | O Krutykh | 6 | 6 | | Q | O Krutykh | 4 | 7 | 6 | | | | | | | | | |
| | M Bašić | 6 | 6 | | | M Bašić | 6 | 5 | 2 | | | | | | | | | |
| | A Santillan | 2 | 2 | | | | | | | Q | O Krutykh | 3 | 6 | 7 | | | | |
| WC | G Lomakin | 3 | 6$^3$ | | | | | | | | N Chappell | 6 | 3 | 5 | | | | |
| | N Chappell | 6 | 7$^7$ | | | N Chappell | 7$^7$ | 6 | | | | | | | | | | |
| Q | B Lock | 3 | 6 | 5 | 2 | S Stakhovsky | 6$^4$ | 4 | | | | | | | | | | |
| 2 | S Stakhovsky | 6 | 3 | 7 | | | | | | | | | | | | | | |