# 2020 Bangkok Challenger II – Singles

James Duckworth was the defending champion but chose not to defend his title.
Federico Gaio won the title after Robin Haase retired in the final trailing 1–6, 6–4, 2–4 in the third set.

## Seeds

All seeds receive a bye into the second round.
* Jiří Veselý (quarterfinals)
* Go Soeda (third round)
* Paolo Lorenzi (second round)
* Antoine Hoang (second round)
* Attila Balázs (third round, retired)
* Zhang Zhizhen (second round)
* Martin Kližan (second round)
* Federico Gaio (champion)
* Sebastian Ofner (second round)
* Robin Haase (final, retired)
* Roberto Marcora (second round)
* Denis Istomin (third round)
* Peter Polansky (third round)
* Dmitry Popko (semifinals)
* Ramkumar Ramanathan (quarterfinals)
* Botic van de Zandschulp (third 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

| Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Semifinals | Semifinals | Semifinals | Semifinals | Final | Final | Final | Final | Final |
| 1 | Jiří Veselý | 6$^3$ | 3 | | | | | | | | | | |
| 8 | Federico Gaio | 7$^7$ | 6 | | | | | | | | | | |
| 8 | Federico Gaio | 7$^7$ | 6 | | 8 | Federico Gaio | 6 | 6 | | | | | |
| | | | | | 14 | Dmitry Popko | 4 | 3 | | | | | |
| 14 | Dmitry Popko | 6 | 6 | | 14 | Dmitry Popko | 4 | 3 | | | | | |
| | Daniel Altmaier | 0 | 4 | | | | | | | | | | |
| | Daniel Altmaier | 0 | 4 | | | | | | 8 | Federico Gaio | 6 | 4 | 4 |
| | | | | | | | | | 10 | Robin Haase | 1 | 6 | 2$^r$ |
| | Roman Safiullin | 6 | 4 | 3 | | | | | | | | | | 10 | Robin Haase | 1 | 6 | 2$^r$ |
| | Hugo Grenier | 2 | 6 | 6 | | | | | | | | | |
| | Hugo Grenier | 2 | 6 | 6 | | Hugo Grenier | 6$^5$ | 3 | | | | | |
| | | | | | 10 | Robin Haase | 7$^7$ | 6 | | | | | |
| 10 | Robin Haase | 7$^7$ | 6 | | 10 | Robin Haase | 7$^7$ | 6 | | | | | |
| 15 | Ramkumar Ramanathan | 6$^5$ | 2 | | | | | | | | | | |

### Top half
#### Section 1

| 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 | J Veselý | 6 | 3 | 6 | | | | | | | | | |
| WC | Thanapet Chanta | 6$^3$ | 0 | | Z Kolář | 4 | 6 | 3 | | | | | | | | | |
| | Z Kolář | 7$^7$ | 6 | | | | | | 1 | J Veselý | 6 | 3 | 6 | | | | |
| | D Yevseyev | 6 | 6 | | | | | | 16 | B van de Zandschulp | 3 | 6 | 4 | | | | |
| WC | P Kovapitukted | 3 | 1 | | D Yevseyev | 6$^5$ | 6 | 4 | | | | | | | | | |
| | | | | 16 | B van de Zandschulp | 7$^7$ | 1 | 6 | | | | | | | | | |
| | | | | | | | | | | | | | | 1 | J Veselý | 6$^3$ | 3 |
| | | | | | | | | | | | | | | 8 | F Gaio | 7$^7$ | 6 |
| | | | | 12 | D Istomin | 6 | 7$^9$ | | | | | | | | | | |
| | S Giraldo | 6 | 4 | | S Giraldo | 3 | 6$^7$ | | | | | | | | | | |
| | G Oliveira | 0 | 1$^r$ | | | | | | 12 | D Istomin | 4 | 2 | | | | | |
| WC | K Samrej | 4 | 3 | | | | | | 8 | F Gaio | 6 | 6 | | | | | |
| Alt | K Uchida | 6 | 6 | Alt | K Uchida | 6 | 6$^5$ | 5 | | | | | | | | | |
| | | | | 8 | F Gaio | 3 | 7$^7$ | 7 | | | | | | | | | |

#### 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 | Quarterfinals |
| | | | | | 3 | P Lorenzi | 3 | 2 | | | | | | | | | | |
| | D-h Lee | 1 | 3 | | | S Mukund | 6 | 6 | | | | | | | | | | |
| | S Mukund | 6 | 6 | | | | | | | | S Mukund | 5 | 4 | | | | | |
| | N Kuhn | 0 | 7$^7$ | 1 | | | | | | 14 | D Popko | 7 | 6 | | | | | |
| Q | A Karatsev | 6 | 6$^4$ | 6 | Q | A Karatsev | 6 | 0 | 4 | | | | | | | | | |
| | | | | | 14 | D Popko | 4 | 6 | 6 | | | | | | | | | |
| | | | | | | | | | | | | | | | 14 | D Popko | 6 | 6 |
| | | | | | | | | | | | | | | | | D Altmaier | 0 | 4 |
| | | | | | 9 | S Ofner | 3 | 2 | | | | | | | | | | |
| | E Karlovskiy | 6 | 6 | | | E Karlovskiy | 6 | 6 | | | | | | | | | | |
| WC | Michael Mathayomchand | 3 | 2 | | | | | | | | E Karlovskiy | 5 | 6 | 3 | | | | |
| | D Altmaier | 6 | 6 | | | | | | | | D Altmaier | 7 | 4 | 6 | | | | |
| | M Jaziri | 2 | 1 | | | D Altmaier | 6 | 6 | | | | | | | | | | |
| | | | | | 7 | M Kližan | 3 | 3 | | | | | | | | | | |

### 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 | Third round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals |
| | | | | | 6 | Zh Zhang | 6 | 1 | 6$^5$ | | | | | | | | | |
| | R Safiullin | 6 | 0 | | | R Safiullin | 3 | 6 | 7$^7$ | | | | | | | | | |
| | Y Bai | 1 | 1$^r$ | | | | | | | | R Safiullin | 6 | 6 | | | | | |
| WC | W Trongcharoenchaikul | 5 | 7$^7$ | 1 | | | | | | WC | W Trongcharoenchaikul | 4 | 4 | | | | | |
| | GM Moroni | 7 | 6$^4$ | 0$^r$ | WC | W Trongcharoenchaikul | 3 | 6 | 6 | | | | | | | | | |
| | | | | | 11 | R Marcora | 6 | 3 | 4 | | | | | | | | | |
| | | | | | | | | | | | | | | | R Safiullin | 6 | 4 | 3 |
| | | | | | | | | | | | | | | | H Grenier | 2 | 6 | 6 |
| | | | | | 13 | P Polansky | 6 | 7 | | | | | | | | | | |
| | V Galović | 3 | 0$^r$ | | | S Sekiguchi | 3 | 5 | | | | | | | | | | |
| | Shuichi Sekiguchi | 6 | 3 | | | | | | | 13 | P Polansky | 6 | 4 | 6$^4$ | | | | |
| | H Grenier | 6 | 6 | | | | | | | | H Grenier | 3 | 6 | 7$^7$ | | | | |
| PR | A De Greef | 1 | 4 | | | H Grenier | 6 | 3 | 6 | | | | | | | | | |
| | | | | | 4 | A Hoang | 0 | 6 | 1 | | | | | | | | | |

#### 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 |
| | | | | | 5 | A Balázs | 6 | 3 | 6 | | | | | | | | |
| Alt | F Peliwo | 5 | 4 | | | F Baldi | 1 | 6 | 4 | | | | | | | | |
| | F Baldi | 7 | 6 | | | | | | | 5 | A Balázs | 4 | 1$^r$ | | | | |
| Q | M Bašić | 3 | 1 | | | | | | | 10 | R Haase | 6 | 2 | | | | |
| | R Olivo | 6 | 6 | | | R Olivo | 3 | 3 | | | | | | | | | |
| | | | | | 10 | R Haase | 6 | 6 | | | | | | | | | |
| | | | | | | | | | | | | | | 10 | R Haase | 7$^7$ | 6 |
| | | | | | | | | | | | | | | 15 | R Ramanathan | 6$^5$ | 2 |
| | | | | | 15 | R Ramanathan | 7$^7$ | 1 | | | | | | | | | |
| | B Gojo | 6$^4$ | 2 | | | JC Aragone | 6$^5$ | 0$^r$ | | | | | | | | | |
| | JC Aragone | 7$^7$ | 6 | | | | | | | 15 | R Ramanathan | 7 | 7 | | | | |
| | I Marchenko | 6 | 5 | 4 | | | | | | 2 | G Soeda | 5 | 5 | | | | |
| Alt | A Molčan | 2 | 7 | 6 | Alt | A Molčan | 6 | 6$^4$ | 2 | | | | | | | | |
| | | | | | 2 | G Soeda | 0 | 7$^7$ | 6 | | | | | | | | |