John Millman, of Australia, returns to Kei Nishikori, of Japan, in the men's tennis competition (AP Photo/Vadim Ghirda)
Montenegro's Suzana Lazovic is stopped during the women's preliminary handball match (AP Photo/Matthias Schrader)
Li Xiaoxia of China plays table tennis (AP Photo/Natacha Pisarenko)
Spain's Liliana Fernandez sets up the ball during a volleyball match (AP Photo/Marcio Jose Sanchez)
United States' Michael Phelps sticks out his tongue as he prepares a men's 200-meter butterfly (AP Photo/Martin Meissner)
Pan Chien-Hung, of Taiwan, competes in the men's weightlifting competition (AP Photo/Mike Groll)
Serghei Cechir, of Moldova, competes in the men's weightlifting competition (AP Photo/Mike Groll)
United States' Michael Phelps' son Boomer wears ear protection during the swimming competitions (AP Photo/Michael Sohn)
Juan Carlos Cabrera, of Mexico, competes in the men's rowing single sculls (AP Photo/Luca Bruno)
France's Luka Karabatic, left, complains that Qatar's Hassan Mabrouk pushed him while on the ground (AP Photo/Ben Curtis)
France's Thierry Omeyer during the men's preliminary handball match (AP Photo/Ben Curtis)
Brazil's Pedro Solberg digs against Canada during a men's beach volleyball match (AP Photo/Marcio Jose Sanchez)
Netherlands' Anicka Van Emden competes in judo competition (AP Photo/Markus Schreiber)
Argentina's Cristian Poglajen spikes the ball (AP Photo/Matt Rourke)
Hungary's Laszlo Csoknyai during the men's 81-kg judo competition (AP Photo/Markus Schreiber)
Qatar's Goran Stojanovic tries to catch the ball during the men's preliminary handball match (AP Photo/Matthias Schrader)
Cuba's Lazaro Alvarez, left, fights Italy's Carmine Tommasone during a men's lightweight 60-kg preliminary boxing match (AP Photo/Frank Franklin II)
Hungary's Katinka Hosszu competes in a semifinal of the women's 200-meter individual medley (AP Photo/Lee Jin-man)
Ching Cheng of Taiwan plays against Li Xiaoxia of China during their table tennis match (AP Photo/Natacha Pisarenko)
Hungary's Katinka Hosszu competes in a women's 200-meter individual medley (AP Photo/Michael Sohn)
France's Cedric Sorhaindo scores a goal past Qatar's Goran Stojanovic during the men's preliminary handball match (AP Photo/Ben Curtis)
Remember this guy? Pita Nikolas Aufatofua was a sensation carrying the flag of Tonga during the opening ceremony. (AP Photo/Matt Slocum)
Belarus' Kylie Rei Dickson performs on the vault (AP Photo/Dmitri Lovetsky)
India's Dipa Karmakar performs on the vault AP (AP Photo/Dmitri Lovetsky)
Slovakia's Barbora Mokosova performs on the vault (AP Photo/Dmitri Lovetsky)
Vietnam's Thi Ha Thanh Phan performs on the vault (AP Photo/Dmitri Lovetsky)
United States' Simone Biles performs on the uneven bars (AP Photo/Julio Cortez)
Japan's Asuka Teramoto performs on the uneven bars (AP Photo/Julio Cortez)
Canada's Isabela Onyshko performs on the vault (AP Photo/Dmitri Lovetsky)
Mexico's Alexa Moreno performs on the uneven bars (AP Photo/Morry Gash)
Canada's Catherine Beauchemin-Pinard competes in judo competition (AP Photo/Markus Schreiber)
United States' Alexander Naddour performs on the floor (AP Photo/Dmitri Lovetsky)
Australia's Emma Tonegato avoids a tackled (AP Photo/Themba Hadebe)
Britain's Kristian Thomas performs on the horizontal bar (AP Photo/Tim Donnelly)
United States' Steele Johnsoncompete in the men's synchronized diving final (AP Photo/Wong Maye-E)
United States' Sam Mikulak performs on the horizontal bar (AP Photo/Dmitri Lovetsky)
Portugal's Telma Monteiroite competes in judo competition (AP)
Portugal's Telma Monteiro celebrates after winning a bronze medal (AP Photo/Markus Schreiber)
Russia's David Belyavskiy performs on the floor (AP Photo/Rebecca Blackwell)
Li Xiaoxia of China plays table tennis (AP Photo/Petros Giannakouris)
Russia's Ekaterina Kosianenko bumps during a women's preliminary volleyball match (AP Photo/Jeff Roberson)
Canada's Samuel Schachter attempts a block against Italy in a men's beach volleyball match (AP Photo/Marcio Jose Sanchez)
Ecuador's Carlos Eduardo Quipo Pilataxi during a men's light flyweight preliminary boxing match (AP Photo/Frank Franklin II)
Australia's Evania Pelite scores a try (AP Photo/Themba Hadebe)
Serbia's Jovana Stevanovic spikes the ball (AP Photo/Jeff Roberson)
New Zealand's Gayle Broughton, left, is challenged by Australia's Alicia Quirk during the women's rugby match (Zsolt Czegledi/MTI via AP)