Poland's Iga Swiatek serves against China's Zheng Qinwen (not in photograph) during their round of 16 match at the Women's Tennis Grand Prix WTA tournament in Stuttgart, southwestern Germany, on April 20, 2023. (PHOTO / AFP)

STUTTGART, Germany - World number one Iga Swiatek of Poland swept past China's Zheng Qinwen here on Thursday in the second round of the tennis WTA 500 Stuttgart Grand Prix.

The defending champion used one hour and 26 minutes to defeat the Chinese rising star 6-1, 6-4, extending her unbeaten run in Stuttgart to five matches.

Playing in her first match in 45 days, Swiatek came back strongly from her injuries and hardly missed a beat to extend her head-to-head record over Zheng to 3-0. The Pole broke the reigning WTA Newcomer of the Year twice in each set to wrap up a straight-set win.

Facing the top player like Iga (Swiatek), I have to deliver the best performance from the very beginning. But today I felt a bit nervous and I was not in the best physical condition. I feel like my moves are a bit slower. It's hard to overturn the match when falling behind.

Zheng Qinwen, Chinese professional tennis player

"She's really talented, and everybody can see that," Swiatek said. "I need to adjust, and I'm just happy that I was focused on myself, on what I wanted to do ... and I feel pretty comfortable."

The 20-year-old Chinese talent told Xinhua that she was dissatisfied with her performance and made some unexpected mistakes.

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"I lost points too quickly and made too many backhand errors, especially in the first set. The first serves were not good as well. I tried to fight back from 2-4 in the second set and that was too late," said Zheng.

"Facing the top player like Iga, I have to deliver the best performance from the very beginning. But today I felt a bit nervous and I was not in the best physical condition. I feel like my moves are a bit slower. It's hard to overturn the match when falling behind."

China’s Zheng Qinwen returns the ball to Poland’s Iga Swiatek (not in photograph) during their round of 16 match at the Women's Tennis Grand Prix WTA tournament in Stuttgart, southwestern Germany, on April 20, 2023. (PHOTO / AFP)

Swiatek moves through to a quarterfinal match against former world number 1 Karolina Pliskova. The Czech outlasted Donna Vekic of Croatia in two hours and 20 minutes through a tiebreak in the third-set to advance.

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"I felt like I need to be 100 percent focused from the beginning to the end, to think about technique and tactics," Swiatek said. "I'm pretty happy that I'm not rusty and I could perform good tennis, even though I had a break."