STUTTGART, Germany – German qualifier Laura Siegemund continued her Stuttgart romp, backing up her first-round upset of Anastasia Pavlyuchenkova with an even bigger win over No.4 seed Simona Halep for a spot in the quarterfinals of the Porsche Tennis Grand Prix.

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“I think it’d be presumptuous to say [the match] was perfect, because there is always something to improve,” Siegemund said. “But that was very good and of course I’m mega happy. I have not expected that it would go so smoothly.”

Halep, who was nursing a left ankle injury she picked up over the Fed Cup weekend during Romania’s 1-4 loss to Germany, was subdued against the German. The Romanian’s normally aggressive baseline play was noticeably absent, hitting only three winners and 10 unforced errors to Siegemund’s 28 and 14, respectively.

But Siegemund was undaunted by both the occasion and her ailing opponent. Playing in front of a local audience in her hometown of Stuttgart, Siegemund allowed Halep only three games in their hour-long match, winning 6-1, 6-2.

“I just played point by point,” the German said. “Sure, it’s definitely the biggest win of my career, but now after the match, I can only say, I have made few mistakes.

“I started very aggressively. That was the plan – attack her serve, tear open the field early. I know I’ve always done that well and it worked very well this time too.”

With the win Siegemund continues her upward momentum: earlier this year she defeated the World No.22 Jelena Jankovic at the Australian Open, and in Charleston she made the quarterfinals of a Premier-level event for the first time.

Siegemund will go on to play against Roberta Vinci in the quarterfinals, the Italian having booked her spot after brushing aside Julia Goerges 6-3, 6-4.