Powerful-serving Julia Goerges stunned top seed Caroline Wozniacki with a straight sets win in the WTA Auckland Classic final on Sunday.

The 29-year-old German, with a first serve topping 180 kilometres per hour (112 miles per hour), sent down 11 aces on her way to winning the Auckland title for the first time in her ninth attempt 6-4, 7-6 (7/4).

It also stretched the world No 14’s winning streak to 14 matches including winning successive WTA tournaments in Moscow and Zhuhai late last year.

Goerges made an immediate statement at the start of each set with service breaks.

Games went with service from there in the first set, which Goerges sealed with her seventh ace.

Wozniacki double faulted at 15-40 at the start of the second set before she began to fight back.

Goerges needed her booming serve to save break points at 2-1 and 3-2 before Wozniacki finally broke through to level at 4-4, sending the set into a tie break which went to the German.

Wozniacki declared she was preparing for a “great” Australian Open as she closed in on regaining the world top ranking despite the surprise defeat.

“I’ve got a lot of matches under my belt this week, it was the preparation I hoped for,” she said.

“Now I can take a day off tomorrow and fly to Melbourne and get used to courts over there, and the conditions, and hopefully it’s going to be a great couple of weeks.”

“Everyone wants to be number one, but it’s something I’ve done before and obviously it would be nice to do it again, but honestly I think i’m just thinking about being in the finals, holding trophies, lifting trophies.”