Moscow, Jan 2 (IANS/RIA Novosti): Promising British youngster Laura Robson was upset in the second round of the Shenzhen Open tennis tournament in China by lower-ranked Romanian Monica Niculescu.

Returning to China for her first tournament of the season, seventh seed Robson, 18, was unable to repeat the form Tuesday that took her to her first WTA final in Guangzhou last year and lost 2-6, 3-6.

World No.58 Niculescu, who won her only WTA title to date in Nantes in October, faces a quarterfinal against either Taiwan's Kai-Chen Chang or Chinese lucky loser Yi-Miao Zhou.

Elsewhere, fourth seed Su-Wei Hsieh's campaign ended with a 3-6, 0-6 defeat in her second-round match against Germany's Annika Beck.

Sixth seed Shuai Peng of China awaits Beck in the quarterfinals after beating Japan's Ayumi Morita 6-1, 6-1.

The other seeds to play Tuesday all progressed to the quarters in straight sets.

Top seed Li Na cruised past Luxembourg's Mandy Minella 6-4, 6-0 in front of her home crowd and now faces eighth seed Bojana Jovanovski of Serbia, who knocked out local wildcard Ying-Ying Duan 6-3, 6-1 in a one-sided affair that took less than an hour.

Czech fifth seed Klara Zakopalova downed her Ukrainian opponent Elina Svitolina 6-4, 6-3 and will play either French second seed Marion Bartoli or Switzerland's Stefanie Voegele in the quarterfinals.

The Shenzhen Open is a $500,000 hard-court tournament that forms part of many players' preparations for the Australian Open later this month.