NEW YORK; Wins for Venus Williams and Kim Clijsters on Friday set up a mouth-watering US Open fourth-round clash between the two former champions.

Third seed Williams, a back-to-back winner here in 2000 and 2001, defied a sore left knee to defeat Magdalena Rybarikova of Slovakia 6-2, 7-5. Unseeded Clijsters, the 2005 champion who is on the comeback trail after two years out of the sport, edged Belgian compatriot Kirsten Flipkens 6-0, 6-2.

Defending champion and tournament favourite Serena Williams also made it into the last 16, beating Spain’s Maria Jose Martinez Sanchez 6-3, 7-5. That put her into a fourth-round clash with Slovakian Grand Slam regular Daniela Hantuchova, who eased past Vania King of the United States 6-2, 6-2.

It was a good day for Italy as Flavia Pennetta swept aside Canada’s Aleksandra Wozniak 6-1, 6-1 and Francesca Schiavone upset eighth seed Victoria Azarenka of Belarus 4-6, 6-2, 6-2. Russian seventh seed Vera Zvonareva saw off compatriot Elena Vesnina 6-2, 6-4 while Li Na kept Asian hopes alive with a 6-4, 6-2 win over Maria Kirilenko of Russia.

On the men’s draw, six-time Grand Slam champion Rafael Nadal and British second seed Andy Murray withstood fightbacks to reach the third round. Spanish third seed Nadal defeated Germany’s Nicolas Kiefer 6-0, 3-6, 6-3, 6-4. Nadal will next play against countryman Nicolas Almagro, who dispatched Robby Ginepri 6-7 (7/9), 6-2, 6-3, 4-6, 6-4.

Murray beat Chile’s Paul Capdeville 6-2, 3-6, 6-0, 6-2. The 22-year-old Scotsman will next play against 196th-ranked US wild card Taylor Dent.

All 16 top seeds advanced to the third round, the first time this has happened in any Grand Slam tournament in the 41-year Open era, as sixth seed Juan Martin del Potro, seventh seed Jo-Wilfried Tsonga, ninth seed Gilles Simon, 11th seed Fernando Gonzalez and 13th seed Gael Monfils also won second-round matches.

Dent outlasted Spain’s Ivan Navarro 6-4, 5-7, 6-7 (1/7), 7-5, 7-6 (11/9). Del Potro beat Austrian Jurgen Melzer 7-6 (8/6), 6-3, 6-3. The Argentine will face Austrian Daniel Koellerer for a place in the last 16.

Spain’s Juan Carlos Ferrero beat German Philipp Petzschner 1-6, 3-6, 6-4, 6-2, 6-4 and Tsonga defeated Finland’s Jarkko Nieminen 7-5, 6-3, 6-4. Chile’s Gonzalez ousted Frenchman Josselin Ouanna 6-4, 6-7 (5/7), 6-3, 6-4 while France’s Monfils blasted 17 aces in defeating Germany’s Andreas Beck 6-3, 7-5, 6-3.