Swimming at the 2016 Summer Olympics – Men's 100 metre freestyle

At 18 years of age, Kyle Chalmers defeated the experienced field of sprinters to become Australia's first Olympic champion in this event since Michael Wenden topped the podium in 1968. Rallying from seventh at the halfway turn, he overhauled the field for the gold medal and a junior world record in 47.58.[2][3] Swimming out of lane seven, Pieter Timmers posted a 47.80 to take home the silver for the Belgians, along with a national record. Meanwhile, U.S. sprinter and defending champion Nathan Adrian barely advanced out of the prelims earlier, but bounced back to earn a bronze in the final with a 47.85.[4][5][6]

Leading the race early on the initial length, Canada's Santo Condorelli narrowly slipped out of the podium to fourth in 47.88, just a 0.03-second deficit behind Adrian.[7] British teenager Duncan Scott finished fifth in 48.01 to match his own national record that he set in the heats.[8] American youngster Caeleb Dressel picked up a sixth spot in 48.02, while Australia's pre-race favorite Cameron McEvoy dropped back to seventh in 48.12.[9] Amid the delight of the home crowd, Brazil's Marcelo Chierighini rounded out the field with an eighth-place time in 48.42.[6]

Notable swimmers missed the final roster, including China's Ning Zetao, the defending World champion, and Russia's Vladimir Morozov, who was allowed to compete in Rio, after filing a successful appeal against his possible doping report ban.[10]

Prior to this competition, the existing world and Olympic records were as follows.

World record	César Cielo (BRA)	46.91	Rome, Italy	30 July 2009	[11][12]
Olympic record	Eamon Sullivan (AUS)	47.05	Beijing, China	13 August 2008	[13]

The competition consisted of three rounds: heats, semifinals, and a final. The swimmers with the best 16 times in the heats advanced to the semifinals. The swimmers with the best 8 times in the semifinals advanced to the final. Swim-offs were used as necessary to break ties for advancement to the next round.[1]