The "Blade Runner" made history at the Olympics on Saturday and the British rowing team did more of the same.

Oscar Pistorius was cheered around the Olympic track Saturday, finishing second in his 400-meter heat to advance to the next round on his carbon fiber blades. The South African double amputee circled the oval with 80,000 fans cheering him on in 45.44 seconds _ good enough for second place in his heat and a berth in the semifinals Sunday night.

The 25-year-old Pistorius was born without fibulas and his legs were amputated below the knee before he was a year old.

"I've worked for six years ... to get my chance," said Pistorius. "I found myself smiling in the starting block."

At the Olympic rowing site west of London, Kat Copeland and Sophie Hosking became the third female British crew to capture gold at the games, winning the lightweight women's double sculls at Dorney Lake.

No British woman had ever won rowing gold at the Olympics before this regatta, but Katherine Grainger and Anna Watkins eased to victory in the double sculls on Friday and Helen Glover and Heather Stanning won the pair on Wednesday.

With the men's four winning their final earlier Saturday, the host nation has four golds and is set to top the rowing medals table.

In another early gold medal Saturday, Nicola Spirig of Switzerland outsprinted Sweden's Lisa Norden in the final meters to win the women's triathlon. Spirig crossed the line after the 10-kilometer run leg just a fraction ahead of Norden, with Erin Densham of Australia taking the bronze.

Later in the day at the Aquatics Centre, an era of unprecedented sporting domination comes to an end when Michael Phelps swims his last competitive race.

Phelps is heavily favored to add one more gold to his collection of 21 Olympic medals, 17 of them gold, when he swims the butterfly leg of the 4x100 medley relay, a race the Americans have never lost.

The 27-year-old swam his first Olympics in Sydney 12 years ago and is retiring after London.

At the All England Club, Maria Sharapova and Serena Williams will both be playing not only for a gold medal, but a so-called Golden Slam. Each is seeking a first Olympic title to add to their career majors.

Williams said she was more concerned with winning another medal for the American Olympic team, than with adding to her list of titles.

"Whether I win or lose, that's not the big deal," Williams said. "The big deal for me, USA is guaranteed another medal. I'm guaranteed to just go out there tomorrow and have fun. That's all I can do."

In the second day of athletics, local favorite Mo Farah runs in the 10,000 meters against stiff competition including Kenenisa Bekele of Ethiopia and another British medal candidate, Jessica Ennis, completes the heptathlon.

The women's 100-meter final will provide another indication of just how fast the track is in the 80,000-seat Olympic Stadium.

Led by world champion Carmelita Jeter's time of 10.83 seconds, seven sprinters _ including defending champion Shelly-Ann Fraser-Pryce of Jamaica _ ran the first round of the 100 in 11 seconds or better on Friday.

Usain Bolt also will begin the defense of his men's 100-meter crown in the first round of heats.

Outside the stadium and in the center of London, the men's 20-kilometer walk ends with a not-very-leisurely stroll along The Mall, the broad, tree-lined avenue running between Buckingham Palace and Trafalgar Square.

Britain aims to continue its dominance on the Siberian pine boards at the Velodrome with the women's team pursuit.