Caroline Wozniacki was extended to three sets before going through in the China Open

Story highlights

Caroline Wozniacki survives scare at China Open before coming through in three sets

Wozniacki beats Lucie Hradecka of Czech Republic 3-6 6-0 7-5 in Beijing

No.1 defends China's Li Na who crashed out at same stage to qualifier

Andy Roddick and Wimbledon champion Petra Kvitova make early exits in ATP/WTA tournament

CNN  — 

Caroline Wozniacki survived a first round scare at the China Open Monday then defended French Open champion Li Na who has been the subject of fierce criticism for exiting at the same stage to a lowly-ranked opponent.

World No.1 Wozniacki looked to be heading the same way as she lost the first set to Czech Lucie Hradecka and wobbled in the decider, but pulled through 3-6 6-0 7-5.

There was no such fortune for Li Sunday as she went out in straight sets to Romanian qualifier Monica Niculescu, a defeat that left a large and partisan home crowd in Beijing stunned.

Li has struggled since her grand slam triumph at Roland Garros in May but Wozniacki understands the weight of expectation.

“I think it’s not pressure, it’s just tough,” Wozniacki told AFP after her narrow victory.

“There are so many girls out there playing great tennis at the moment.

“They have nothing to lose, so it’s kind of being a target. Everyone is aiming to win against you. It’s never easy.”

Li, who also reached the final of the Australian Open, has been given a hard time on internet message boards since her shock defeat, but Wozniacki believes she will shrug it off.

“I’m sure when she looks back on the season, she’s very proud and very happy. I don’t think she’s looking at the internet too much and reading about herself – at least I don’t,” added the 21-year-old Dane, the subject of sniping herself after failing to win a grand slam.

In other action Monday at the $4.5 million WTA and ATP event, there was a welcome home victory for Zheng Jie as she beat Alberta Brianti of Italy 4-6 6-17-5.

Former top-ranked Ana Ivanovic continued her recent improved form with a 6-2 6-3 win over Svetlana Kuznetsova of Russia but Wimbledon champion Petra Kvitova later joined Li Na as a first round casualty as she fell 7-6 6-3 to Sofia Arvidsson of Sweden.

In the men’s tournament, there was the first big upset as big-hitting Kevin Anderson of South Africa put out Andy Roddick of the United States, 6-4 7-5, with the sixth seed describing his performance as “unacceptable” while Marin Cilic of Croatia thrashed Wu Di of China 6-2 6-0.