The United States and Brazil both won in the second round to stay undefeated at the women's volleyball world championships.

Destinee Hooker scored a team-high 19 points as the Americans defeated the Czech Republic 25-20, 25-20, 25-13 in Group F on Saturday to improve to a perfect 6-0. The Czechs dropped to 3-3.

"It was good timing for us against a Czech team that has been playing well, U.S. coach Hugh McCutcheon said. "They have many ways they can attack you. Destinee Hooker played well. Her performance today depended upon the play of a lot of others."

Sheilla Castro scored 21 points as Olympic champion Brazil also improved to 6-0 with a 25-19, 25-19, 25-16 win over Thailand. Brazil will play Cuba on Sunday.

"We did well in serves and counterattacks, Brazil coach Jose Guimaraes said. "We have to think about Cuba tomorrow. They are always a tough match for us. Our goal here is to make the final."

Elsewhere, the Netherlands defeated Cuba 25-12, 22-25, 25-12, 25-20 to improve to 4-2. Cuba dropped to 2-4.

In Group E, defending champion Russia overpowered Peru 25-15, 25-15, 25-20 while Poland downed South Korea 12-25 25-17 25-18 22-25 17-15.