# 2023 Zadar Open – Singles

Flavio Cobolli was the defending champion but lost in the semifinals to Sebastian Ofner.
Alessandro Giannessi won the title after defeating Ofner 6–4, 5–7, 7–6$^{(8–6)}$ in the final.

## Seeds

* Tseng Chun-hsin (second round)
* Jozef Kovalík (second round)
* Ryan Peniston (first round)
* Sebastian Ofner (final)
* Flavio Cobolli (semifinals)
* Laurent Lokoli (withdrew)
* Vít Kopřiva (first round)
* Manuel Guinard (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 | Final | Final | Final | Final | Final |
| 5 | Flavio Cobolli | 5 | 5 | | | | | |
| 4 | Sebastian Ofner | 7 | 7 | | | | | |
| 4 | Sebastian Ofner | 7 | 7 | 4 | Sebastian Ofner | 4 | 7 | 6$^6$ |
| | | | | | Alessandro Giannessi | 6 | 5 | 7$^8$ |
| | Alessandro Giannessi | 6 | 6 | | Alessandro Giannessi | 6 | 5 | 7$^8$ |
| | Arthur Cazaux | 3 | 4 | | | | | |

### 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 | C-h Tseng | 6 | 7 | | | | | | | | | | | | | | | |
| LL | N Milojević | 4 | 5 | | 1 | C-h Tseng | 6 | 1 | 4 | | | | | | | | | |
| Q | G Zeppieri | 6 | 6 | | Q | G Zeppieri | 4 | 6 | 6 | | | | | | | | | |
| Q | D Pichler | 1 | 4 | | | | | | | Q | G Zeppieri | 6 | 2 | 1 | | | | |
| | FC Jianu | 1 | 6$^4$ | | | | | | | 5 | F Cobolli | 3 | 6 | 6 | | | | |
| | D Džumhur | 6 | 7$^7$ | | | D Džumhur | 6 | 2 | 5 | | | | | | | | | |
| WC | M Poljičak | 1 | 3 | | 5 | F Cobolli | 3 | 6 | 7 | | | | | | | | | |
| 5 | F Cobolli | 6 | 6 | | | | | | | | | | | | 5 | F Cobolli | 5 | 5 |
| 4 | S Ofner | 7$^7$ | 2 | 6 | | | | | | | | | | | 4 | S Ofner | 7 | 7 |
| | N Fatić | 6$^1$ | 6 | 2 | 4 | S Ofner | 1 | 7$^7$ | 6 | | | | | | | | | |
| | M Zekić | 6 | 3 | 2 | | DN Mădăraș | 6 | 6$^3$ | 4 | | | | | | | | | |
| | DN Mădăraș | 2 | 6 | 6 | | | | | | 4 | S Ofner | 6 | 6 | | | | | |
| Q | J Ocleppo | 3 | 6 | 4 | | | | | | | M Gigante | 4 | 1 | | | | | |
| | M Gigante | 6 | 2 | 6 | | M Gigante | 6 | 6 | | | | | | | | | | |
| | H Međedović | 6 | 6 | | | H Međedović | 1 | 2 | | | | | | | | | | |
| 7 | V Kopřiva | 4 | 2 | | | | | | | | | | | | | | | |

### Bottom half

| First round | First round | First round | First round | First round | Second round | Second round | Second round | Second round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Semifinals | Semifinals | Semifinals |
| 8 | M Guinard | 4 | 2 | | | | | | | | | | | | |
| | A Giannessi | 6 | 6 | | | A Giannessi | 7$^7$ | 6 | | | | | | | |
| | N Serdarušić | 6 | 6 | | | N Serdarušić | 6$^4$ | 3 | | | | | | | |
| | G Mager | 4 | 2 | | | | | | | A Giannessi | 7$^8$ | 6 | | | |
| LL | S Caruso | 3 | 7$^7$ | 6 | | | | | | Z Piros | 6$^6$ | 2 | | | |
| | K Coppejans | 6 | 6$^4$ | 1 | LL | S Caruso | 2 | 3 | | | | | | | |
| | Z Piros | 6 | 6 | | | Z Piros | 6 | 6 | | | | | | | |
| 3 | R Peniston | 4 | 4 | | | | | | | | | | A Giannessi | 6 | 6 |
| Q | G Fonio | 6 | 4 | 2 | | | | | | | | | A Cazaux | 3 | 4 |
| | A Cazaux | 4 | 6 | 6 | | A Cazaux | 6 | 6 | | | | | | | |
| | T Droguet | 4 | 6 | 4 | WC | D Ajduković | 3 | 4 | | | | | | | |
| WC | D Ajduković | 6 | 3 | 6 | | | | | | A Cazaux | 6 | 6 | | | |
| WC | D Prižmić | 6 | 6 | | | | | | WC | D Prižmić | 1 | 1 | | | |
| Q | M Bašić | 1 | 3 | | WC | D Prižmić | 6 | 6 | | | | | | | |
| Q | Jeremy Jahn | 7 | 3 | 2 | 2 | J Kovalík | 3 | 4 | | | | | | | |
| 2 | J Kovalík | 5 | 6 | 6 | | | | | | | | | | | |