Misty May-Treanor and Kerri Walsh Jennings advanced to the semifinals of the Olympic beach volleyball tournament with a straight-set win Sunday.
American teammates April Ross and Jennifer Kessy also moved on without losing a set at Horse Guards Parade.
May-Treanor and Walsh Jennings, the two-time reigning Olympic champions, used power and touch to knock off the Italians Greta Cicolari and Marta Menegatti 21-13, 21-13 in 33 minutes.
May-Treanor and Walsh Jennings remained undefeated at the Olympics and will face 2008 bronze medalists Zhang Xi and Xue Chen in the semis.
"We have fine-tuned our play, our sonars are working," said Walsh Jennings, "but every day the competition will get tougher."
Ross and Kessy's match stretched to 49 minutes after Czechs Marketa Slukova and Kristyna Kolocova won four straight points to narrow the second-set score to 18-15.
Slukova and Kolocova fought off two set points at 20-18 before Ross' spike ended the match and gave the Americans a 25-23, 21-18 win.
They moved on to face Brazilians Juliana Silva and Larissa Franca, who beat Germans Laura Ludwig and Sara Goller 21-10, 21-19 in the nightcap.
Zhang and Xue won 21-18, 21-11 over Stefanie and Doris Schwaiger, the Austrian sisters who were the first team ever to win an Olympic set off May-Treanor and Walsh Jennings earlier this week.