Michael Phelps has claimed his 19th gold medal at the Olympic Games, helping Team USA to victory in the men's 4x100m freestyle event.
The 31-year-old, who is the most decorated athlete in Olympic history, came out of retirement in 2014 in order to compete at his fifth Games.
Team USA topped the podium with a time of 3:09.92, helped by Phelps's second-leg contribution of 47.12s and reaction time of just 0.08s.
Silver went to France, who were 0.61s back, while bronze went the way of Australia, who clawed their way back from fifth in the final leg thanks to Cameron McEvoy's contribution of 47.00s.
Phelps will have three more chances to add to his medal collection in Rio when he competes in the 100m butterfly, 200m butterfly and 200m individual medley.
