Martinez Sanchez defeated the top-seeded Wozniacki 7-5, 6-4 to capture her second career WTA singles title. Her first title was in February when she beat Argentina's Gisela Dulko in the Bogota final.
"I'm very happy about my win today and how I played," Martinez Sanchez said. "It was really windy but I think that helped me, because I like to serve and volley and Caroline played more from the baseline. I'm really proud I was able to beat the No. 9 player in the world. It was a great week for me."
Wozniacki was seeking her sixth career singles championship. She won tournaments this year at Ponte Vedra Beach and Eastbourne, while also losing in finals matches at Memphis, Charleston, S.C., and Madrid.