Mia Blichfeldt matched World No.1 An Se-young in the first set, but it wasn't enough to create what would have been a huge upset at the Badminton World Championships.
The Dane, who is ranked 16th in the world, lost 16-21, 10-21.
Blichfeldt won several long and tough duels in the first set and had the world's strongest female badminton player on the ropes for periods.
The will and belief was certainly there, but An Se-young made very few mistakes. So when she pulled away from 15-15, it was as if Blichfeldt lost her composure.
There is no room for that against the South Korean, who was much more convincing in the second set.
The reigning Olympic champion is in search of the second World Championship title of her career. For now, she is ready for a quarter-final.
Later on Wednesday, several other Danes will be in action. This applies to Rasmus Gemke and Anders Antonsen in men's singles, Line Christophersen in women's singles, and three doubles.