American swimming phenom Katie Ledecky swam into Olympic history on the seventh day of the Rio games, while her teammate Michael Phelps -- already a living legend -- suffered a rare setback in his quest for Olympic gold.
Ledecky, who at 19 remains one of the youngest swimmers at the games, won the women's 800-meter freestyle race in world-record time on August 12. She obliterated her own record by nearly two seconds to triumph in 8 minutes, 4.79 seconds.
Moreover, the win gave her the rare feat of matching an Olympic record that has stood for 48 years -- fellow American Debbie Meyer's feat of winning the 200-meter, 400-meter, and 800-meter Olympic freestyles at the 1968 Games in Mexico City.
It was Ledecky's fourth gold at Rio, adding to a pile of medals that is sure to keep growing in the years ahead.
"I'm so proud to be part of history," Ledecky said afterward. "I just wanted to lay it all out there.... It was my last swim here at the Olympics, the pinnacle of our sport, and I have to wait another four years to have that moment."
But while Ledecky was celebrating, swimming giant Phelps made a rare slip and ceded first place in the 100-meter men's butterfly race to Joseph Schooling of Singapore, giving the tiny city-state its first-ever gold medal in the event.
Phelps, 31, who has said he will retire after the Rio Olympics with his unprecedented 22 Olympic gold medals, insisted after the race that he was satisfied with a silver medal at his final individual swimming event.
"I'm happy," Phelps said. "I've been able to do everything I've ever put my mind to in the sport, and after 24 years in the sport, I'm happy with how things finished."
In other highlights, Anthony Ervin of the United States reclaimed the mantle of fastest man in the water by taking the 50-meter freestyle gold medal 16 years after he first won it.
Rafa Nadal and Marc Lopez of Spain won the Olympic men's doubles tennis title, beating Romania's Florin Mergea and Horia Tecau to secure their country's third gold medal of the Games.
Iranian weightlifter Kianoush Rostami broke his own world record to win gold in the men's 85-kilogram weightlifting event, clinching Iran's first medal of the games.
Germany's Isabell Werth became the most successful rider in Olympic history when she won her sixth gold medal as part of the German dressage team.
Outside the stadium, a German Olympic canoe coach was fighting for his life after a car accident left him with serious head injuries.
Stefan Henze, a canoe slalom silver medalist at the 2004 Games, underwent emergency surgery in a Rio de Janeiro hospital.
The German Olympic Sports Confederation said the injuries, sustained while riding in a Rio taxi, are life threatening.