Former world number one Caroline Wozniacki beat unseeded French challenger Kristina Mladenovic to take the Hong Kong Open on Sunday after a battle of wills that lasted almost three hours.

Wozniacki of Denmark, seeded fifth in the competition, stormed the first set 6-1 with Mladenovic visibly despondent and limping slightly.

The 23-year-old French woman emerged in the second set with her right leg bandaged and renewed focus, forcing Wozniacki to dive around the court with a combination of drop shots and powerful drives.

The set went to 6-6, with Mladenovic sealing the tie-break 7-4 to go even.

Spectators around the packed stadium flickered paper fans constantly on a hot and humid afternoon, with temperatures at 30 degrees Celsius (86 degrees Fahrenheit).

Dressed all in green, a determined Wozniacki finally sealed victory in the third set as a tired Mladenovic was ultimately unable to match the Dane's power and consistency.

Frequently bending to lean on her racquet between points, the Frenchwoman was in tears as she desperately tried to fight back after Wozniacki took a 5-0 lead.

Wozniacki eventually took the final set 6-2.

It was the latest strong performance in a resurgent season which saw her reach the semi-finals of the US Open and win the Pan Pacific Open in Tokyo.

Wozniacki had downed seventh seed Jelena Jankovic, also a former world number one, to book her final place.

Mladenovic had been aiming for her first WTA title -- it was the third time she had made a competition final only to lose.

She had beaten Australian Daria Gavrilova, seeded eighth in Hong Kong, to secure her place in the final.

Venus Williams and current world number one Angelique Kerber went out earlier in the competition.