Alexei Popyrin defeated Stan Wawrinka in the final, 6–7(5–7), 6–3, 6–4 to win the singles tennis title at the 2023 Croatia Open Umag. It was his second ATP Tour singles title.
Jannik Sinner was the reigning champion, but chose not to defend his title.
Seeds The top four seeds received a bye into the second round.
Draw
Finals
Top half
Bottom half
Qualifying Seeds
Qualifiers
Qualifying draw
First qualifier
Second qualifier
Third qualifier
Fourth qualifier
References
External links Main draw Qualifying draw