Japan's Kosuke Hagino held off a brilliant fightback from United States' Chase Kalisz to win the Olympic men's 400m individual medley.
Hagino, who won IM bronze in 2012, held the lead following the backstroke and touched home just ahead of Kalisz in a time of four minutes 06.95 seconds.
Kalisz took silver in 4:07.75 and Hagino's team-mate Daiya Seto was third in 4:09.71.
Great Britain's Max Litchfield, 21, in his first Games, was fourth in 4:11.62.
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