BEIJING -- Chinese women duo Zhang Xi/Xue Chen and men's tandem Wu Penggen/Xu Linyin made top 16 on Tuesday after scoring their respective second preliminary victory.

Tian Jia/Wang Jie clinched their top 16 place on Monday after their second preliminary win.

Wu/Xu bounced back from the loss of the first set, edging past Estonian pair Kais/Vesik in three sets (15-21,21-11 and 15-13).

China's Xue Chen jubilates after her team defeated Germany in their women's preliminary pool D beach volleyball match at Beijing's Chaoyang Park beach volleyball ground during the 2008 Beijing Olympic Games on August 12, 2008. China won 2-0. [Agencies] More photos

"We were a little strained at first and the defense of the rivals also exerted big pressure," commented the 1.98-meter Wu on their first set loss. "In next matches we'll play in a more relaxed way and play to our best standard," said Wu.

The victory came after their first preliminary win on Sunday over Gosch/Horst of Austria. Also in Group A, Pablo Herrera/Raul Mesa beat Florian Gosch/Alexander Horst on Tuesday, securing a berth in top 16.

Zhang/Xue won over the rivals in a much easier match, outclassing German duo Goller/Ludwig in two straight sets (21-14, 21-18).

Besides the battle between the Chinese and Estonian pairs, the fourth preliminary day also witnessed other matches in which the winners came from behind to defeat the other side.

In men's Group D, Brazilian pair Araujo/Magalhaes won the first set but was defeated by Doppler/Gartmayer of Austria finally.

In women's Group F, Mexico's  Bibiana Candelas/Mayra Garcia fought back from the first set loss, beating Vassiliki Arvaniti/Vasso Karadassiou of Greece 2-1.

Japanese pair Kentaro Asahi/Katsuhiro Shiratori also played three sets before defeating Emiel Boersma/Bram Ronnes of the Netherlands. The two sides drew in the first two sets.

In women's Group B, defending champions Misty May-Treanor beat Cuban pair Dalixia Grasset/Tamara Peraza, while Nila Hakedal/Ingrid Torlen of Norway edged out Chiaki Kusuhara/Mika Teru Saiki of Japan.

In other women's matches, South Africa's Judith Augoustides/Vitalila Nel was defeated by Greek pair Efthalia Koutroumanidou/Maria Tsiartsiani, while Brazil's Talita Antunes/Renata Ribeiro won over Doris Schwaiger/Stefanie Schwaiger of Austria.

In other men's competitions, Dmitri Barsouk/Igor Kolodinsky of Russia thrashed Italy's Eugenio Amore/Ricardo Lione in two sets. Jake Gibb/Sean Rosenthal of the United States met Julius Brink/Christoph Dieckmann of Germany and presented a fierce battle with the Americans winning the match 2-0.