Not a great birthday present for Wozniacki who turned 19 on Saturday. She had to be content with a price cheque, a smaller cup and a heartfelt rendition of "Happy Birthday" by the near 4300 people in the audience.
For Martinez Sanchez, winning her second WTA Tour title and advancing from 54 to 42 in the world ranking, the tournament in Sweden has been her best this year.
"I have felt completely at home here and I certainly hope to return," she told Swedish News Agency TT after the match.
The men's Swedish Open Tennis tournament starts on Monday.