Eric Murray and Hamish Bond are now double Olympic champions after powering through the opposition in the final of the men's pair.
The perfect pair headed home South Africa and Italy to win by 2.8 seconds and defend the title they won in London four years ago.
They were third through the opening 500m behind South Africans Lawrence Brittain and Shaun Keeling but then opened up a half a length gap over the Italian duo of Giovanni Abagnale and Marco do Costanzo by the halfway stage.
From then on the race was not about who would win but who would grab the minor medals.
Bond and Murray stamped their authority on the field over the third quarter to open up a 6.5sec lead at the 1500m and although South Africa closing the gap by the finish, they were never seriously threatened in winning by more than a length.
The duo were unbackable favourites to win after going unbeaten since 2009 and have now won 69 consecutive races.
The medal comes as a welcome boost to the rowing squad after both men's and women's doubles crews failed to reach their final despite being medal hopes.
The rowers have a target of matching the five medals they claimed in London four years ago and have seven other crews in finals, including the men's lightweight four later on Thursday.