London (CNN) -- With 50 meters to go, it looked like Oscar Pistorius was cruising to gold in the men's 200 meters.
But then, to his outside, a flash of green went by, a 20-year-old Brazilian who rocketed past him to upset the most famous Paralympian of all time.
Alan Fonteles Cardoso Oliveira beat Pistorius to the line, winning gold in 21.45. South Africa's Pistorius took silver in 21.52, unable to come near his world record set Saturday. The bronze went to Blake Leeper of the United States.
On Saturday, the third day of the Games, Pistorius blazed through the men's 200-meter-T44 qualifier with a world-record time of 21.30 seconds. The Paralympic movement classifies events, using terms like T44, to group competitors based on their disability.
Pistorius, who uses carbon fiber prosthetic blades, made it to the semifinals of the individual 400-meter and the 400-meter relay final at the Olympics last month, running against athletes with no disablities.
Besides the 200-meter run, he will also compete in the Paralympics in the men's 100-meter-T44 (set for Wednesday and Thursday) and the 400-meter-T44 (happening Friday and Saturday), both of which he won in Beijing four years ago.
Pistorius, nicknamed the Blade Runner, is also part of South Africa's 4x100-meter T42/T46 relay team, which is scheduled to race Wednesday.
U.S. two-sport athlete Rudy Garcia-Tolson, a day after finishing ninth in the men's 200 meters (T42) on the track, won a silver in the 200-meter individual medley. Yevheniy Bohodayko of Ukraine won the event in a world record time of 2:33.13. Garcia-Tolson set an American record of 2:33.94.
Jessica Long of the United States, who was looking to add a fourth gold medal in swimming in the games, finished fifth in the 50-meter freestyle (S8). Her teammate, Mallory Weggemann, won the event in 31.13, edging 13-year-old Maddison Elliott of Australia.
Long, a 20-year-old from Baltimore, is entered in nine events in the meet. She won three gold medals in Athens at age 12 and four more in Beijing. She also has a silver and bronze from 2008, giving her 12 career Paralympic Games medals.
Long was born in Siberia with fibular hemimelia, meaning she had no fibulas and other bones in lower legs, according to her website. She was adopted by her U.S. parents at age 13 months and had her lower legs amputated five months later.
Australian Jacqueline Freney won her third gold medal with a world record in the women's 200-individual medley (SM7).
At the weightlifting venue, Fatma Omar of Egypt set a world record in women's powerlifting. The 38-year-old won her 56-kilogram (123-pound) division with a lift of 140 kilograms (309 pounds).
New Zealand's Phillipa Gray and Laura Thompson also set a world record Sunday in the qualification round of the women's individual B pursuit, an event on a tandem bicycle for the visually impaired. They won the final, beating the Irish team of Catherine Walsh and Francine Meehan.
China has a huge lead in medals, topping the table with 87. The Chinese added to their total on Sunday with golds in table tennis from Feng Panfeng in men's singles (Class 3) and Liu Jing in women's singles (Class 1-2). China also took golds in rowing's mixed doubles sculls and men's single sculls from Huang Cheng, the world record holder.
Great Britain is second in medals with 53.
CNN's Steve Almasy, Laura Smith-Spark and Tom McGowan contributed to this report.