U.S. swimmer Michael Phelps, the most decorated Olympian of all time, gestures after winning the 200-meter butterfly on Tuesday, August 9. It was the 20th gold medal of his Olympic career. Later in the night, Phelps won his 21st gold -- and his 25th medal in all -- after swimming the anchor leg in the 4x200 freestyle.
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Phelps' win in the 200-meter butterfly avenged one of the few losses of his Olympic career -- a second-place finish to South Africa's Chad Le Clos in 2012. Le Clos finished fourth in Tuesday's race.
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American Katie Ledecky smiles after winning the 200-meter freestyle. It is her second gold in the Rio Games. She also won the 400-meter freestyle.
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Ukrainian tennis player Elina Svitolina reacts after her third-round victory over top-ranked Serena Williams. Svitolina won 6-4, 6-3.
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Williams won gold in singles and doubles in the 2012 Olympics. But she is already out of both tournaments in Rio de Janeiro.
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U.S. gymnasts -- from left, Gabby Douglas, Madison Kocian, Simone Biles, Aly Raisman and Laurie Hernandez -- celebrate after winning the team all-around. The United States also won gold in 2012.
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Brazilian basketball player Marcus Marquinhos, in green under the basket, tips in the winning basket to upset Spain 66-65.
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Synchronized divers Chen Ruolin and Liu Huixia won the 10-meter platform event for China.
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The diving pool, right, had turned from blue to green since Monday. The cause is still under investigation, but water tests showed there were no health risks, Rio organizers said.
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Egyptian beach volleyball players Doaa Elghobashy and Nada Meawad, left, switch sides with Italy's Marta Menegatti and Laura Giombini.
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Kosovo's Majlinda Kelmendi, right, defeated Italy's Odette Giuffrida in the 52-kilogram (115-pound) judo final. It is the first Olympic medal in Kosovo history.
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Japanese rugby player Katsuyuki Sakai scores a try against Great Britain.
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Brazilian rider Ruy Fonseca, on Tom Bombadill Too, hits an obstacle during the jumping round of the team eventing final.
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Australia's Rowie Webster, right, mugs Russia's Anna Timofeeva during a water polo match.
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Japanese canoeist Takuya Haneda is congratulated after a ride in the C-1 slalom final. He won the bronze medal.
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Germany's Sideris Tasiadis competes in the C-1 slalom.
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Mexico's Jorge Alejandro Barajas serves the ball during a volleyball match against France.
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Italy's volleyball team is introduced before its match against the United States.
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Iran's Zahra Nemati shoots an arrow during the women's individual archery competition.
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Hungarian fencer Geza Imre, left, competes against France's Gauthier Grumier during an epee semifinal. Imre won 15-13 to advance to the final, which he lost to South Korea's Park Sang-young.
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Moldovan weightlifter Serghei Cechir celebrates after finishing in first place in the 69-kilogram (152-pound) weight class. He lifted 144 kilograms (317.5 pounds) in the snatch and 178 kilograms (392.4 pounds) in the clean and jerk for a combined 322 kilograms (709.9 pounds).
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The Ivory Coast's Thibault Amani Danho competes in the 100-meter freestyle.
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Mexico's Misael Uziel Rodriguez, left, takes a battering from Iraq's Waheed Abdulridha Waheed Karaawi during a middleweight boxing match. Rodriguez won the match, however, and advanced.
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Track cyclists from Great Britain put their heads down during a training session inside the Olympic Velodrome.
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Zimbabwe's Sean Michael Gunn dives in for a 100-meter freestyle race.
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South Korean archer Chang Hye-jin takes part in the women's individual competition. Earlier this week, she and teammates Choi Mi-sun and Ki Bo-bae took gold in the team event.
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Volleyball player Demian Gonzalez is embraced by Argentina fans after his team beat Russia in a preliminary round. They will next face Poland on Thursday.
