Rio de Janeiro, Aug 13 (IANS): Hosts Brazil crushed South Korea 3-0 (25-17, 25-13, 27-25) to remain unbeaten at the Rio 2016 Olympics women's volleyball tournament.

With the 4-0 win-loss record, Brazil top Pool A and assured a spot in the quarterfinals. Russia, who also remain perfect in the group stage, was second with 12 points and booked a spot in top eight as well, reports Xinhua.

But the loss leaves Japan to have to win their last group game against Argentina for the last available ticket to the next stage.

The United States, Serbia, the Netherlands and China have qualified from Pool B.

Nataliya Goncharova and Tatiana Kosheleva led the way for Russia with 20 points and 12 each. Captain Saori Kimura was Japan's best scorer with 12 points. Russia outplayed Japan in blocking 11-7, serving 6-4 and attacking 49-36.

Argentina edged Cameroon 3-2, which means they still have the chance to enter the quarterfinals after they beat Japan on Sunday.

In a Pool B match on Friday, World Cup winners China suffered their second loss as they fell to Serbia 3-0 (25-19, 25-19, 25-22) .

Tijana Boskovic had 17 kills, three blocks and three aces to lift the World Cup runners-up up to a sweet revenge for their 3-1 loss to the Chinese women in their World Cup encounter last year. Brankica Mihajlovic added 19 points.

Serbia improved to a 3-1 win-loss record in pool B while China dropped to 2-2. Both teams have secured their berth in the quarter-finals.

China will play their last preliminary Pool B match against the United States on Sunday. The Americans trounced Italy 3-1 to stand on the top of the pool with no loss. The Netherlands whitewashed Puerto Rico 3-0.