Hsieh took the final match 2-6, 7-5, 4-1 when Martic retired. Martic was in her sixth set of the day and had been on the court for nearly 5 hours Sunday when play stopped.
The fatigue was showing as Martic landed just 26 percent of her first serves in the third set against Hsieh, who was up a break in the set.
Rain was an issue throughout the tournament and forced the semifinal, scheduled for Saturday, between Martic and second-seeded Jelena Jankovic to be pushed to Sunday.
That was a tight 258-point, 3-hour, 7-minute affair in which Martic squeezed out a 6-7 (5-7), 7-5, 7-6 (7-5) win.
Martic grabbed the advantage in the final with a solid first set in which she dropped just six points on serve and had two breaks. Hsieh evened the match with a late second-set break and had taken 63 percent of the points in the third set when the match ended.
Hsieh, a 26-year-old who turned professional in 2001, had 17 ITF titles on her resume but Sunday marked her first WTA win. She collected $37,000 for the Malaysian Open win. Martic, 21, was also appearing in her first WTA final, earned $19,000 as the runner-up