Defending champions Brazil were stunned by South Korea in straight sets, while another title favourite United States stayed unbeaten in the women’s volleyball tournament of the London Olympics.

Wing spiker Kim Yeon-Koung steered the Koreans past the Brazilians 25-23, 25-21, 25-21, Xinhua reports.

The Koreans played fast attack with delicate organisation by setter and captain Kim Sa-Nee, while the Brazilians committed too many errors Wednesday.

“We lost because of Korea’s excellent blocking and the precision of their serves. We have just got to be both more energetic and aggressive in our play,” said Brazil’s star player, opposite hitter Sheilla Castro.

Wednesday’s fiasco cast a shadow over Brazil’s outlook for quarterfinals. The team was ranked fifth of the six-team Pool B with two losses. However, the Brazilians keep their confidence alive.

“We made a lot of mistakes, but it is not time yet to panic. We know the situation is poor because we have lost the last two matches, but there is still time to correct our mistakes. We are still alive,” said wing spiker Paula Pequeno.

While Brazil was striving to enter the top eight, U.S. proved their world No. 1 strength beating China 3-0 to register their third win.

The Chinese, once champions in 2004 Athens Games and bronze winner in Beijing, lost the match 24-26, 16-25, 29-31, to the might Americans.

Wing spikers Destinee Hooker and Megan Hodge were both on top form for U.S. Hookers stored the highest 22 points and China’s young opposite hitter Zeng Chunlei, a surprising substitution when China was in inferiority, took 10 points.

With the third win, U.S. booked a berth in the quarterfinals, while China kept the hopes alive with two victories over Serbia and Turkey.

In another Pool B match, desperate Turkey, who suffered two losses, upset Serbia 3-0 to keep their chance for quarterfinals alive, while it turns extremely difficult for the Serbians from here on.

In Pool A, Japan beat Dominican Republic 25-20, 25-19, 25-23 while Russia upset Algeria 25-7, 25-14, 25-15 to top the group with three victories.

Ruthless Italy defeat host Great Britain in straight sets to take the second place in the group.

Twelve women’s teams are divided into two groups in the preliminary round of the Olympic tournament that runs through July 28 to Aug 11.

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