Top seed Jelena Jankovic reached the quarter-finals of the China Open on Wednesday with a 6-3, 7-5 victory over Canada's [Images] Aleksandra Wozniak, while Zheng Jie restored some pride for the host nation.

The Serbian world number two will meet seventh seed Daniela Hantuchova [Images] of Slovakia, who was pushed all the way in her 6-1, 0-6, 7-5 win over tenacious Thai Tamarine Tanasugarn.

On a cool evening in Beijing [Images] that saw both players sporting long sleeves, Jankovic was the quickest to warm up, taking an early break to wrap up the first set and then racing to a 5-2 lead in the second.

World number 39 Wozniak denied the US Open [Images] finalist a quick victory, however, breaking back twice to level at 5-5, before surrendering the match with a string of unforced errors.

Hantuchova shivered for two hours and 12 minutes in an entertaining battle with Tanasugarn, rating it one of the toughest matches of her career.

"I even felt fog on my mouth and my legs couldn't move in the second set. It was a wise decision to wear (sweatpants) in the third set," she told reporters.

After watching four of her compatriots bundled out of the first round on Tuesday, China's Zheng battled a head cold to upset world number 10 Agnieszka Radwanska of Poland.

Zheng, who carried over a first-set 3-0 lead after rain stopped play on Tuesday, wasted no time pressing her advantage, winning 6-2, 6-3 to reach the second round.

In the men's competition, fifth seed Fernando Verdasco set up an all-Spanish second round meeting with former world number one Juan Carlos Ferrero after overpowering American Bobby Reynolds 6-3, 6-3.

After enjoying first-round byes, former US. Open champion Andy Roddick [Images] and top seed David Ferrer of Spain will bid for quarter-final places on Thursday.

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