U.S. gymnasts, left to right, Simone Biles, Gabrielle Douglas, Lauren Hernandez, Madison Kocian and Aly Raisman stand for their national anthem Tuesday during the medal ceremony for the artistic gymnastics women's team competition. Associated Press/Julio Cortez

U.S. divers Jessica Parratto, left, and Amy Cozad compete during the women's synchronized 10-meter platform diving final. Associated Press/Wong Maye-E

Serena Williams shows her frustration during her loss Tuesday to Elina Svitolina of Ukraine in the third round of the women's singles tennis tournament at the 2016 Summer Olympics.

Edwin Orlando Mosquera Roa of Colombia competes in the men's 69kg weightlifting competition at the 2016 Summer Olympics in Rio de Janeiro.

Turkey's Busra Katipoglu competes against Macedonia's Katerina Nikoloska during the women's 63-kg judo competition.

Mexico's Samuel Cordova (13) spikes the ball as France's Earvin Ngapeth, lower left, and Kevin le Roux (10) block during a men's preliminary volleyball match.

Bernhard Sieber and Paul Sieber, of Austria, rest after competing in the men's rowing lightweight double sculls repechage heat.

Uzbekistan's Hurshid Tojibaev, top, fights Britain's Joseph Cordina during a men's light weight 60-kg preliminary boxing match.

The United States' Madison Keys celebrates after defeating Spain's Carla Suarez Navarro in tennis.

Gabor Bockzo of Hungary, left, and Alexandre Bouzaid of Senegal compete in the men's individual epee event.

Italy's Carmine Tommasone, left, falls as he fights Cuba's Lazaro Alvarez during a men's lightweight 60-kilogram preliminary boxing match at the 2016 Summer Olympics.

U.S. gymnasts, left to right, Gabrielle Douglas, Lauren Hernandez, Aly Raisman and Simone Biles celebrate at the end of the artistic gymnastics women's team final Tuesday in Rio de Janeiro. The team repeated as the gold medal winner. Associated Press/Charlie Riedel

Katie Ledecky celebrates after winning the gold medal in the women's 200-meter freestyle. Associated Press/Michael Sohn

Michael Phelps celebrates after winning the gold medal in the men's 200-meter butterfly. Associated Press Photo/Michael Sohn

Michael Phelps competes in the final of the men's 200-meter butterfly. Associated Press/Lee Jin-man