China's Zheng Qinwen hits a return to Belarus' Victoria Azarenka during their women's singles match at the WTA Adelaide International tennis tournament in Adelaide on January 5, 2023. (Photo: AFP)

CANBERRA, Jan. 11 (Xinhua) -- China's Zheng Qinwen has withdrawn from the Adelaide International in order to prepare for the Australian Open.

Zheng pulled out of the second tournament in Adelaide on Wednesday after losing the first set of her second round match against two-time Wimbledon champion Petra Kvitova 7-6 (6).

The 20-year-old Chinese appeared to pull her left thigh in her 4-6, 6-4, 6-0 win over Shelby Rogers of the United States in the first round and showed up in Wednesday's second round match with bandages wrapped around her thigh.

It was the rising Chinese star's sixth match in eight days ahead of the Australian Open, which starts on Monday.

Kvitova saved three set points in the tie break before winning the opener.

The walkover means the Czech, currently ranked 16th in the world, remains undefeated in four matches in 2023 - her most successful start to a year since 2011.

"Of course, this gives me some good confidence," Kvitova said.

"I'm happy that my wrist is much better than this time last year. That's great news. I hope I'm going to stay healthy, but so far it's okay."

The match was followed on center court by eight seed Belinda Bencic's 6-3, 6-3 win against Anna Kalinskaya.

Bencic, the reigning Olympic gold medalist, broke serve five times in the victory and has lost only two sets in her last eight matches.

"I'm really strong in the most important matches and in tight moments, so I definitely feel very confident about that. It's just really something about when you have a lot of matches you also feel better, and you have to believe in yourself in the tight moments," she said on Wednesday.

The Swiss will play either world number four Caroline Garcia or Katerina Siniakova in the quarter-finals while Kvitova will face the winner between Daria Kasatkina and Barbora Krejcikova.