Kiwi rower Mahe Drysale has defended his single sculls title in dramatic fashion, beating Crotian Damir Martin in a photo-finish.
In a nail-biting end to the final at Rodrigo de Freitas lagoon, both rowers were given the same official time but Drysdale was announced the winner after officials studied a photo of the finish.
Drysdale, 37, pumped his fist when the result was confirmed, two minutes after finishing.
It is his third Olympic medal, following bronze in Beijing and gold in London.
Martin led the race for the first 1400m before Drysdale powered in front.
Victory seemed to be his before European champion Martin came again, hitting the line at greater speed than Drysdale but a fraction too late.
Ondrew Synek of the Czech Republic was third.