The 21-year-old Barthel, ranked 64th, closed with an ace on match point. She had a first-serve percentage of 82 percent in the final.

Barthel also beat second-seeded Anabel Madinah Garrigues, No. 4 seed Angelique Kerber and defending champion Jarmila Gajdosova of Australia.

Barthel, who won three qualifying and five main draw matches at Hobart, will play her doubles partner Anne Keothavong in the first round of the Australian Open in Melbourne on Monday.

"I have to relax now a little bit and of course I will celebrate," she said. "I've never been there (Melbourne Park) before, so I will look everywhere and see and then I will try to have a hit, try to get used to the courts." She is beginning to believe in her ability to win big matches.

"I did it once now so I can do it maybe another time," she said. "I think I can go even one step further."

The final of the Sydney International was postponed because of wet weather on Saturday.

Finland's Jarkko Nieminen and France's Julien Benneteau will now meet at 10am on Sunday, local time, complicating the travel plans of both players for the Australian Open which starts on Monday.

World number 49 Benneteau's first match at Melbourne Park, against Slovakia's Karol Beck, is not scheduled until Tuesday but Nieminen has been drawn to play on Margaret Court Arena in the night session on Monday.

The world number 77 will barely have been in Melbourne for 24 hours when he takes the court against Argentina's David Nalbandian.

Nieminen's situation is complicated by also being in the doubles final. That match, between Nieminen and Australia's Matthew Ebden versus the American pairing of Bob and Mike Bryan, will follow the singles, delaying his departure from Sydney even longer.