BEIJING Even by the lofty standards of the Williams sisters, three victories at the Olympics is a good day's work.

They won in singles and doubles Tuesday, and the toughest match was the one they played together. Venus and Serena rallied in first-round doubles to beat Iveta Benesova and Nicole Vaidisova of the Czech Republic 4-6, 7-5, 6-1.

Earlier, the Williamses won second-round singles matches. Serena beat Samantha Stosur of Australia 6-2, 6-0, and Venus swept Benesova 6-1, 6-4. The sisters could meet in Saturday's singles final. “That would be fantastic,” Venus said.

In men's singles, Roger Federer and Rafael Nadal both advanced with ease, with Nadal dropping only three games total against Australian Lleyton Hewitt. Federer next faces Tomas Berdych of the Czech Republic, who beat him at the last Olympics.

James Blake, the lone remaining U.S. player in men's singles, also won, as did No. 3 seed Novak Djokovic of Serbia.

Americans Lindsay Davenport and Liezel Huber won their first-round doubles match, as did the No. 1-seeded men's duo, Mike and Bob Bryan of the United States.

In women's singles, Jelena Jankovic moved atop the rankings and celebrated with a win.

Swimming

Federica Pellegrini of Italy won the 200-meter freestyle, lowering her own world record set a day earlier. She won in 1 minute, 54.82 seconds. Sara Isakovic of Slovenia took the silver, and Pang Jiaying of China earned the bronze. Katie Hoff of the U.S. was fourth, the first time in three events she failed to medal.

Stephanie Rice of Australia won the 200-meter individual medley, lowering her own world record and adding to her victory in the 400 IM. She won in 2 minutes, 8.45 seconds. Kirsty Coventry of Zimbabwe took the silver, and Natalie Coughlin of the U.S. won the bronze, her third medal of the games. Hoff was fourth.

Softball

The Americans beat Venezuela 11-0 for their 15th straight Olympic victory. Jennie Finch was the pitching star, and Natasha Watley, Crystl Bustos and Caitlin Lowe hit homers.

Boxing

World champion flyweight Rau'Shee Warren worked four years to become the first two-time American boxing Olympian in 30 years. Then, in his first match, he made the huge mistake of spending the last 35 seconds trying to protect a lead when he actually was behind and needed to go on the attack. He lost 9-8 to Lee Ok-sung of South Korea and left the ring in tears.

“I don't even know what happened,” Warren said.

Canoe-kayak

U.S. paddlers failed to win medals in men's kayak and men's single canoe in whitewater slalom racing, with canoeist Benn Fraker of Peachtree City, Ga., finishing sixth in the finals. Gold medals went to canoeist Michal Martikan of Slovakia and kayaker Alexander Grimm of Germany. Jack Horan

Diving

Teenagers Chen Ruolin and Wang Xin of China won the women's 10-meter synchronized platform title. Americans Mary Beth Dunnichay and Haley Ishimatsu, both 15, were fifth among eight teams.

Women's soccer

Heather O'Reilly scored 40 seconds into the match, leading the U.S. past New Zealand 4-0 and into the quarterfinals. Better yet, they won their group, avoiding a match with title contender Brazil. The quarterfinals slate: U.S. vs. Canada; Brazil vs. Norway; Sweden vs. Germany; and China vs. Japan.

Equestrian

American Gina Miles, riding McKinlaigh, won the individual silver medal in eventing. Gold went to German Hinrich Romeike, riding Marius.

TV ratings

NBC's first four nights of broadcasts from the Beijing Games have averaged 30.4million viewers during primetime, Nielsen Media Research says. That's 5million more viewers than NBC drew during the comparable period of the '04 Athens Games.