Olympic best

Usain Bolt of Jamaica looks at Andre De Grasse of Canada as they compete in the men's 100m semifinal. REUTERS/Kai Pfaffenbach

Britain's Kate Archibald, Laura Trott, Elinor Barker and Joanna Rowsell compete in the women's team pursuit cycling. REUTERS/Paul Hanna

USA's Katie Ledecky swims with a big lead on her way to winning the gold and setting a new world record in the 800m freestyle. REUTERS/Stefan Wermuth

(From L) Jhoanis Portilla of Cuba, Orlando Ortega of Spain and Deuce Carter of Jamaica compete in the men's 110m hurdles preliminary in the rain. REUTERS/Lucy Nicholson

Photographers work from the tribune during the swimming competition. REUTERS/Athit Perawongmetha

Mohamed Flissi of Algeria competes during men's fly 52kg boxing. REUTERS/Yves Herman

Shaunae Miller of Bahamas throws herself across the finish line to win the gold ahead of Allyson Felix of the U.S. in the women's 400m final. REUTERS/Fabrizio Bensch

Sailors compete under the Christ the Redeemer statue REUTERS/Brian Snyder

First placed Eliud Kipchoge of Kenya celebrates with supporters after the marathon. REUTERS/Athit Perawongmetha

Roman Vlasov of Russia celebrates winning the gold medal after the victory over Mark Overgard Madsen of Denmark in the 75kg greco-roman wrestling. REUTERS/Toru Hanai

Simone Biles of the U.S. during the women's team artistic gymnastics final. REUTERS/Damir Sagolj

Qiu Bo of China competes in the 10m platform. REUTERS/Michael Dalder

Emma Coburn of the U.S. celebrates with supporters after winning bronze in the women's 3000m steeplechase. REUTERS/Dylan Martinez

Gold medalist Jemima Sumgong of Kenya and silver medalist Eunice Jepkirui Kirwa of Bahrain celebrate after the women's marathon REUTERS/Dylan Martinez

Doaa Elghobashy of Egypt and Kira Walkenhorst of Germany compete int he preliminary beach volleyball event. REUTERS/Lucy Nicholson

Ruta Meilutyte of Lithuania competes in the 100m breaststroke. REUTERS/Michael Dalder

Karem Achach and Nuria Diosdado of Mexico compete in the synchronized swimming duets preliminary. REUTERS/Michael Dalder

Michael Phelps of the U.S. reacts after winning gold in the 4 x 100m medley relay bringing his career total to 23 golds. REUTERS/Dominic Ebenbichler

Samir Ait Said of France breaks his leg during competition on the vault. REUTERS/Athit Perawongmetha

Kenya Yasuda of Japan is injured in men's water polo. REUTERS/Laszlo Balogh

Serena Williams reacts during her match against Elina Svitolina of Ukraine. The Olympic champion and world number one tumbled out of the Rio singles competition in the third round on Tuesday after a shock defeat to Svitolina. REUTERS/Toby Melville

Brianna Rollins of the U.S. celebrates winning the gold medal with silver medalist compatriot Nia Ali and bronze medallist Kristi Castlin in the 110m hurdles. REUTERS/Kai Pfaffenbach

Sara Dosho of Japan celebrates with her coach after winning the gold medal in the wrestling final. REUTERS/Toru Hanai

Nikki Hamblin of New Zealand stops running during the race to help fellow competitor Abbey D'Agostino of USA after D'Agostino suffered a cramp in the women's 5000m preliminary. REUTERS/Kai Pfaffenbach

Germany's Erik Heil and Thomas Ploessel celebrate bronze medal in the men's skiff 49er. REUTERS/Brian Snyder

Spiros Gianniotis of Greece kisses the camera after finishing the 10km marathon swim. REUTERS/Carlos Barria

Mutaz Essa Barshim of Qatar reacts after winning silver in the high jump final. REUTERS/Kai Pfaffenbach

Journalists surround a car carrying U.S. Olympic swimmers Jack Conger and Gunnar Bentz as they leave a police station after being questioned in Rio de Janeiro, August 18, 2016. REUTERS/Bruno Kelly

Blanka Vlasic of Croatia competes in the high jump. REUTERS/Dominic Ebenbichler

Miles Gerek Meinhardt the U.S. competes against Artur Akhmatkhuzin of Russia in the men's foil team semifinals. REUTERS/Issei Kato

Mo Farah of Britain celebrates winning the 5,000m. REUTERS/Dylan Martinez

Yuriy Cheban of Ukraine celebrates in the water after winning the gold medal in the men's 200m canoe. REUTERS/Marcos Brindicci

Usain Bolt of Jamaica and Andre De Grasse of Canada compete in the 200m semifinals. REUTERS/Lucy Nicholson

The court is cleaned by personnel as matches were delayed due to rain at the Olympic Tennis Centre. REUTERS/Toby Melville

Neymar of Brazil celebrates with goalkeeper Weverton after they won the penalty shootout and the gold medal against Germany. REUTERS/Leonhard Foeger

Simone Manuel of the U.S. (L) and Canada's Penny Oleksiak (R) touch the wall to tie for the gold medal in the 100m freestyle. Picture rotated 180 degrees. REUTERS/Athit Perawongmetha F

The coach of Mandakhnaran Ganzorig of Mongolia takes off his clothes as he protests after the men's wrestling match against Ikhtiyor Navruzov of Uzbekistan. REUTERS/Toru Hanai

Simone Biles of the U.S. competes on her way to gold in the vault during the women's individual all-around final. REUTERS/Dylan Martinez

Rafaela Silva of Brazil celebrates winning Brazil's first gold in the 57kg judo final. REUTERS/Kai Pfaffenbach

The Maracana Olympic Stadium during the opening ceremony is seen from the Mangueira favela slum. REUTERS/Ricardo Moraes

Giorgio Avola of Italy celebrates winning his foil match. REUTERS/Issei Kato

Yu Mengyu of Singapore eyes the ball during table tennis play against Kim Song I of North Korea. REUTERS/Alkis Konstantinidis

The Refugee Olympic Athletes' team arrives for the opening ceremony. REUTERS/Kai Pfaffenbach

Emilie Andeol of France reacts in the women's 78kg judo medal ceremony. REUTERS/Murad Sezer

Cyrille Maret of France receives congratulations after winning the bronze medal. REUTERS/Toru Hanai

Jennifer Oeser of Germany watches as athletes compete in 10,000m final. REUTERS/David Gray

Mike Rodgers, Justin Gatlin and Tyson Gay react after being disqualified along with Trinidad and Tobago. TV pictures showed U.S. runner Trayvon Bromell stepping into Usain Bolt's lane in the run to the line. REUTERS/Lucy Nicholson

Mariana Pajon of Colombia leads the BMX final. REUTERS/Paul Hanna

Kevin Durant of the U,S, reacts after dunk as Marko Simonovic of Serbia reacts. REUTERS/Jim Young

Caster Semenya of South Africa celebrates after winning the 800m final. REUTERS/Ivan Alvarado

Ruth Beitia of Spain celebrates winning gold in the high jump. REUTERS/Dominic Ebenbichler

Gregorio Paltrinieri of Italy celebrates winning the gold with compatriot Gabriele Detti who won the bronze in the 1,500m freestyle. REUTERS/Stefan Wermuth

Carli Lloyd of the U.S. is consoled by teammate Megan Rapinoe after the game. REUTERS/Ueslei Marcelino

Diana Taurasi of the U.S. hugs team mate Angel McCoughtry after winning the gold in basketball. REUTERS/Jim Young

Laurine van Riessen of the Netherlands and Virginie Cueff of France compete in the women's keirin cycling. REUTERS/Paul Hanna

Gold medal winner Wang Zhen of China (R) celebrates with silver medal winner and compatriot Cai Zelin after the 20km race walk . REUTERS/Sergio Moraes

Kristin Armstrong of the U.S. celebrates with her son after winning her third gold medal in women's cycling time trial. REUTERS/Matthew Childs

2016 Rio Olympics - Synchronised Swimming - Teams - Technical Routine Final - Maria Lenk Aquatics Centre - Rio de Janeiro, Brazil - 16/08/2016. Team Ukraine (UKR) competes. This image has been rotated 180 degrees. REUTERS/Michael Dalder FOR...more

A general view of the Olympic diving pool and the pool for the waterpolo and synchronized swimming. The water in the Olympic diving pool appeared to turn a bright green hue on Tuesday, causing puzzlement among divers and audiences as the women's 10...more

Lee Eun-Ju of South Korea (R) takes a selfie picture with Hong Un Jong of North Korea. REUTERS/Dylan Martinez

Brazilian women's rugby player Isadora Cerullo melted hearts when she accepted a marriage proposal from her girlfriend at the medals ceremony for the first Olympic rugby sevens competition. Television cameras and photographers captured the moment...more

Michael Phelps of the U.S. congratulates Joseph Schooling of Singapore after Schooling won the gold in the 100m butterfly. REUTERS/Dominic Ebenbichler

Britain's Andy Murray reacts as a boy runs on to the court to ask him for an autograph, after he won his match against Juan Monaco of Argentina. REUTERS/Kevin Lamarque

Mathlynn Sasser of Marshall Islands celebrates int he women's 58kg weightlifting competition. REUTERS/Yves Herman

Performers take part in the Opening Ceremony. REUTERS/Lucy Nicholson

Japan's Prime Minister Shinzo Abe takes part in the flag handover ceremony. The 2020 Olympics will be held in Tokyo, Japan. REUTERS/Yves Herman

Wilhem Belocian of France reacts after being disqualified for a false start. REUTERS/Alessandro Bianchi

Silver medalist Renaud Lavillenie of France reacts during the medal ceremony for the pole vault. REUTERS/Sergio Moraes

Inika McPherson of the U.S. rests as she prepares to compete in the high jump. REUTERS/Kai Pfaffenbach

Kei Nishikori of Japan is reflected in a window as he serves against Albert Ramos of Spain. REUTERS/Toby Melville

Kohei Uchimura of Japan falls as he competes on the horizontal bar. REUTERS/Dylan Martinez

Zheng Shuyin of China celebrates after defeating Maria Espinoza of Mexico. REUTERS/Peter Cziborra

Michael Phelps poses with his gold medal for the 4 x 200m freestyle relay. REUTERS/Dominic Ebenbichler

A performer takes part in the opening ceremony. REUTERS/Stefan Wermuth

Fireworks explode during the opening ceremony REUTERS/Pawel Kopczynski