Holly McPeak and Elaine Youngs use deceptive offense. Misty May and Kerri Walsh rely on keeping the focus on themselves.
The two U.S. women's pairs advanced to the quarterfinals with straight-set victories.
The fourth-ranked McPeak and Youngs defeated 12th-seeded Eva Celbova and Sona Novakova of the Czech Republic, 21-16, 21-16. May and Walsh, the No. 1 seeds, beat seventh-seeded Chinese duo Tian Jia and Wang Fei, 21-11, 21-18.
One more victory for each and the friendly rivals, who have been attending each other's matches, would meet in tomorrow's semifinals.
For that to happen, May and Walsh have to beat Canadians Guylaine Dumont and Annie Martin, and McPeak and Youngs have to defeat Germans Stephanie Pohl and Okka Rau in today's quarterfinals.
"You can't look ahead. You'll lose," Walsh said. "It's easy to stay focused."
May and Walsh have yet to drop a set in four matches in Athens, playing with seamless chemistry and committing few unforced errors.
"As long as Kerri and I do what we want on our side, people can do what they want on the other," May said.
American men Dax Holdren and Stein Metzger, upset winners over fourth-ranked Germans Markus Dieckmann and Jonas Reckermann on Friday, face fifth-seeded Swiss pair Patrick Heuscher and Stefan Kobel in today's quarterfinals.