# 2021 Almaty Challenger – Singles

Lorenzo Giustino was the defending champion but lost in the first round to Timofey Skatov.
Zizou Bergs won the title after defeating Skatov 4–6, 6–3, 6–2 in the final.

## Seeds

* Andrej Martin (quarterfinals)
* Mohamed Safwat (first round)
* Kimmer Coppejans (quarterfinals)
* Enzo Couacaud (second round)
* Lorenzo Giustino (first round)
* Dmitry Popko (semifinals, retired)
* Denis Istomin (second round)
* João Menezes (second 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 | Final | Final |
| 6 | Dmitry Popko | 7 | 3 | 1$^r$ | | | | | |
| | Zizou Bergs | 5 | 6 | 5 | | | | | |
| | Zizou Bergs | 5 | 6 | 5 | | Zizou Bergs | 4 | 6 | 6 |
| | | | | | WC | Timofey Skatov | 6 | 3 | 2 |
| | Tseng Chun-hsin | 2 | 3 | | WC | Timofey Skatov | 6 | 3 | 2 |
| WC | Timofey Skatov | 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 | Semifinals |
| 1 | A Martin | 6 | 6 | | | | | | | | | | | | | | | | |
| WC | B Zhukayev | 2 | 1 | | 1 | A Martin | 6 | 6 | | | | | | | | | | | |
| | B Schnur | 6 | 6 | | | B Schnur | 2 | 2 | | | | | | | | | | | |
| | T-l Wu | 4 | 4 | | | | | | | 1 | A Martin | 5 | 3 | | | | | | |
| | T Gabashvili | 1 | 3 | | | | | | | 6 | D Popko | 7 | 6 | | | | | | |
| Q | FC Jianu | 6 | 6 | | Q | FC Jianu | 5 | 3 | | | | | | | | | | | |
| Q | V Orlov | 2 | 3 | | 6 | D Popko | 7 | 6 | | | | | | | | | | | |
| 6 | D Popko | 6 | 6 | | | | | | | | | | | | 6 | D Popko | 7 | 3 | 1$^r$ |
| 3 | K Coppejans | 6 | 6 | | | | | | | | | | | | | Z Bergs | 5 | 6 | 5 |
| Alt | R Ortega Olmedo | 1 | 2 | | 3 | K Coppejans | 2 | 6 | 6 | | | | | | | | | | |
| | N Serdarušić | 5 | 1 | | | GM Moroni | 6 | 3 | 1 | | | | | | | | | | |
| | GM Moroni | 7 | 6 | | | | | | | 3 | K Coppejans | 3 | 6 | 4 | | | | | |
| | Z Bergs | 2 | 7$^{11}$ | 6 | | | | | | | Z Bergs | 6 | 2 | 6 | | | | | |
| | MT Barrios Vera | 6 | 6$^9$ | 3 | | Z Bergs | 6 | 6 | | | | | | | | | | | |
| | E Tiurnev | 3 | 1 | | 8 | J Menezes | 3 | 4 | | | | | | | | | | | |
| 8 | J Menezes | 6 | 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 |
| 7 | D Istomin | 3 | 6 | 6 | | | | | | | | | | | | | | |
| | M Bašić | 6 | 4 | 2 | 7 | D Istomin | 6$^7$ | 4 | | | | | | | | | | |
| | C-h Tseng | 6 | 6 | | | C-h Tseng | 7$^9$ | 6 | | | | | | | | | | |
| | F Meligeni Alves | 2 | 1 | | | | | | | | C-h Tseng | 7$^7$ | 6 | | | | | |
| | D Kuzmanov | 6 | 6 | | | | | | | | D Kuzmanov | 6$^1$ | 3 | | | | | |
| | A Menéndez Maceiras | 2 | 4 | | | D Kuzmanov | 7 | 6 | | | | | | | | | | |
| Q | V Sachko | 7$^7$ | 5 | 2 | 4 | E Couacaud | 5 | 0 | | | | | | | | | | |
| 4 | E Couacaud | 6$^2$ | 7 | 6 | | | | | | | | | | | | C-h Tseng | 2 | 3 |
| 5 | L Giustino | 4 | 6 | 2 | | | | | | | | | | | WC | T Skatov | 6 | 6 |
| WC | T Skatov | 6 | 3 | 6 | WC | T Skatov | 1 | 6 | 6 | | | | | | | | | |
| WC | D Yevseyev | 6 | 4 | 7 | WC | D Yevseyev | 6 | 1 | 4 | | | | | | | | | |
| | R Bonadio | 4 | 6 | 5 | | | | | | WC | T Skatov | 4 | 7$^{10}$ | 6 | | | | |
| Q | E Furness | 1 | 6 | 6 | | | | | | Q | E Furness | 6 | 6$^8$ | 4 | | | | |
| | C Gimeno Valero | 6 | 2 | 3 | Q | E Furness | 6 | 6 | | | | | | | | | | |
| | P Krstin | 6 | 6 | | | P Krstin | 3 | 1 | | | | | | | | | | |
| 2 | M Safwat | 4 | 0 | | | | | | | | | | | | | | | |