# 2021 Challenger Città di Lugano – Singles

This was the first edition of the tournament.
Dominic Stricker won the title after defeating Vitaliy Sachko 6–4, 6–2 in the final, and as No. 874 became the lowest-ranked champion in Challenger history.

## Seeds

* Yūichi Sugita (semifinals)
* Evgeny Donskoy (first round)
* Peter Gojowczyk (first round)
* Marc Polmans (first round)
* Illya Marchenko (first round)
* Roman Safiullin (quarterfinals)
* Yannick Maden (withdrew)
* Roberto Marcora (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 | Final |
| 1 | Yūichi Sugita | 7 | 4 | 4 | | | | |
| WC | Dominic Stricker | 5 | 6 | 6 | | | | |
| WC | Dominic Stricker | 5 | 6 | 6 | WC | Dominic Stricker | 6 | 6 |
| | | | | | Q | Vitaliy Sachko | 4 | 2 |
| Q | Vitaliy Sachko | 7 | 6 | | Q | Vitaliy Sachko | 4 | 2 |
| Alt | Altuğ Çelikbilek | 5 | 0 | | | | | |

### 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 | Y Sugita | 6 | 7 | | | | | | | | | | | | | | | | |
| | J Lenz | 2 | 5 | | 1 | Y Sugita | 7$^8$ | 6$^1$ | 6 | | | | | | | | | | |
| | A Menéndez Maceiras | 7$^7$ | 4 | 3 | WC | L Riedi | 6$^6$ | 7$^7$ | 4 | | | | | | | | | | |
| WC | L Riedi | 6$^5$ | 6 | 6 | | | | | | 1 | Y Sugita | 7$^7$ | 4 | 7$^7$ | | | | | |
| LL | J Sels | 2 | 6 | 1 | | | | | | | E Karlovskiy | 6$^4$ | 6 | 6$^2$ | | | | | |
| | E Karlovskiy | 6 | 1 | 6 | | E Karlovskiy | 6 | 6 | | | | | | | | | | | |
| | A Santillan | 1 | 6 | 6 | | A Santillan | 4 | 3 | | | | | | | | | | | |
| LL | R Peniston | 6 | 1 | 3 | | | | | | | | | | | 1 | Y Sugita | 7 | 4 | 4 |
| 3 | P Gojowczyk | 4 | 6 | 4 | | | | | | | | | | | WC | D Stricker | 5 | 6 | 6 |
| Q | T van Rijthoven | 6 | 4 | 6 | Q | T van Rijthoven | 7 | 4 | 6$^7$ | | | | | | | | | | |
| | J Clarke | 4 | 4 | | WC | D Stricker | 5 | 6 | 7$^9$ | | | | | | | | | | |
| WC | D Stricker | 6 | 6 | | | | | | | WC | D Stricker | 6 | 6 | | | | | | |
| | H Moriya | 1 | 6 | 7 | | | | | | | D Masur | 2 | 4 | | | | | | |
| SE | M Bachinger | 6 | 3 | 5 | | H Moriya | 6 | 2 | 1 | | | | | | | | | | |
| | D Masur | 7$^7$ | 7 | | | D Masur | 4 | 6 | 6 | | | | | | | | | | |
| 5 | I Marchenko | 6$^1$ | 5 | | | | | | | | | | | | | | | | |

### 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 |
| 6 | R Safiullin | 6 | 6 | | | | | | | | | | | | | | | |
| WC | J Kym | 4 | 2 | | 6 | R Safiullin | 6 | 6 | | | | | | | | | | |
| Alt | J Sock | 6 | 6 | | Alt | J Sock | 4 | 3 | | | | | | | | | | |
| Q | A Bellier | 4 | 3 | | | | | | | 6 | R Safiullin | 4 | 3 | | | | | |
| | S Stakhovsky | 6 | 6 | | | | | | | Q | V Sachko | 6 | 6 | | | | | |
| Q | F Forti | 4 | 2 | | | S Stakhovsky | 3 | 1 | | | | | | | | | | |
| Q | V Sachko | 2 | 6 | 6 | Q | V Sachko | 6 | 6 | | | | | | | | | | |
| 4 | M Polmans | 6 | 4 | 2 | | | | | | | | | | | Q | V Sachko | 7 | 6 |
| 8 | R Marcora | 4 | 6$^3$ | | | | | | | | | | | | Alt | A Çelikbilek | 5 | 0 |
| | H Grenier | 6 | 7$^7$ | | | H Grenier | 6 | 4 | 7 | | | | | | | | | |
| | B Tomic | 6 | 6 | | | B Tomic | 4 | 6 | 5 | | | | | | | | | |
| | A Vukic | 4 | 3 | | | | | | | | H Grenier | 6 | 4 | 3 | | | | |
| Alt | L Miedler | 7$^7$ | 6 | | | | | | | Alt | A Çelikbilek | 4 | 6 | 6 | | | | |
| | L Lacko | 6$^0$ | 4 | | Alt | L Miedler | 1$^r$ | | | | | | | | | | | |
| Alt | A Çelikbilek | 4 | 6 | 6 | Alt | A Çelikbilek | 4 | | | | | | | | | | | |
| 2 | E Donskoy | 6 | 2 | 1 | | | | | | | | | | | | | | |