BEIJING - Favourites Cuba and Brazil powered into the women`s volleyball semi-finals in straight sets on Tuesday, edging one step closer to their gold medal goals.

Brazil`s Fabiana Claudino (C, #9) smashes the ball against Japan`s Miyuki Takahashi (L) and Erika Araki (R) during their women`s volleyball quarterfinal match against Japan at the 2008 Beijing Olympic Games on August 19, 2008. Brazil won 3-0. [Agencies]

Cuba, which swept their Group A matches, won 26-24 25-19 26-24 against Serbia in the packed Capital Gymnasium, but the Caribbean side almost faltered in the hard-fought first and third sets.

"Although we won, our players had been under tremendous mental pressure. We`ll do better than this in the next two matches," said head coach Antonio Perdomo, acknowledging the team`s many errors in front of a crowd cheering the underdog.

Brazil`s 25-12 25-20 25-16 win was much more comfortable, with their powerful spikes overcoming resistance from a persistent Japanese side, whose players were in tears after the match.

"Yes, I think about that. We are in the medal zone. That`s important," Brazilian head coach Jose Roberto Guimaraes said when asked about the team`s ambitions for gold.

Brazil did not lose a single set in their Group B matches and the successive wins appear to have made captain Helia Souza even more confident.

"We cannot choose our opponent in the matches ahead, but we`ll be prepared to defeat any," Souza said.

In the semi-finals, Brazil will be pitched against the winner of the quarter-final match between defending champions China and Russia at 1200 GMT.

The long-time rivals staged a classic final match in Athens, with China stealing a thrilling win from Russia after losing the first two sets.

The United States will play Italy at 1400 GMT in the last quarter-final match and the winner will meet Cuba for a place in the final.