Beijing: Holder Caroline Wozniacki survived a tough challenge to begin her title defence of the ATP-WTA China Open Monday, with the top seed stretched to the limit in a win over Lucie Hradecka 3-6, 6-0, 7-5.

Wozniacki, the top-ranked player on the WTA but without a Grand Slam crown, has had a patchy few months, winning a minor pre-US Open title, stalling in the semi-finals of the New York major and then crashing to a second-round loss last week in Tokyo.

But Beijing has a special place for the Dane, winner of six titles this season, who first took over the top ranking in the Chinese capital a year ago.

Wary of the first-round upset loss of French Open winner Li Na of China, Wozniacki made sure she came through for victory over her 49th-ranked opponent from the Czech Republic, but not before dropping the first set.

However, the 21-year-old belatedly came good, ignoring nine aces from her opponent, who also sent over seven double-faults. Wozniacki broke six times on her way to victory and a meeting with Australian Jarmila Gajdosova.

In other first-round matches, Zheng Jie earned a welcome home win as she beat Italian Alberta Brianti 4-6, 6-1, 7-5, while Russian Maria Kirilenko, the 2005 winner, beat German Julia Goerges 7-6 (11/9), 6-3.

Virginie Razzano of France reached the second round by beating Argentine Gisela Dulko 6-2, 6-3.

Austrian Tamira Paszek booked the first of the third-round places with her defeat of Czech Petra Cetkovska 1-6, 6-4, 6-2.

In men's first-round play, three Europeans advanced.

Croatia's former top 10 regular Marin Cilic, now standing 25th, defeated China's Wu Di 6-2, 6-0, while Spain's Feliciano Lopez put out Turk Marsel Ilhan 6-2, 7-6 (8/6).

Florian Mayer of Germany, playing his first match since winning the clay Bucharest title eight days ago, made a successful change of surface to the hardcourts, taking out Spaniard Albert Ramos 6-2, 6-4.

Cilic said the conditions suited him well. "Inside today there was no wind, I had to adjust to the sun and the shade but after a few games it was fine.

"Wu's a very good, talented young player. I practised with him last year, and he can hit the ball well," he said.

Cilic said that while his game has slipped, he believes it's on the mend.

"I feel my form is rising since July. I've had some really good tournaments and good wins against top players. So I'm feeling confident.

"I played well today and I'm looking forward for my next match. It won't be easy, but I hope I'm going to be 100 percent ready," he said of his clash against either second seed Gael Monfils or Italian Fabio Fognini.