Laura Trott became the first British woman to win three OIympic gold medals by helping Great Britain to a world record-breaking victory in the team pursuit on Saturday.
Trott, Joanna Rowsell Shand, Elinor Barker and Katie Archibald comfortably defeated the United States in 4min 10.236sec to retain the title they won in London four years ago.
Trott is now one of Britain's most successful ever female Olympians and has the opportunity to move clear on her own when she bids for a fourth gold in the omnium on Monday and Tuesday.
She said: "It feels incredible. You try not to think about it coming into a race but people were tweeting me and writing articles about it.
"It almost feels like I shouldn't have achieved it in a way. I still feel like that young girl that started down at Welwyn Wheelers."
Rowsell Shand now has two gold medals, having also been part of the triumphant pursuit team at London 2012, while Barker and Archibald win their first.
The United States and then Britain both broke the world record in the semi-finals to set up a potentially thrilling decider.
The American quartet of Sarah Hammer, Kelly Catlin, Chloe Dygert and Jennifer Valente made a flying start and were 0.394 seconds up after only 500m of the 4km distance, but then Britain turned on the turbos and were just 0.096 seconds down after 1km and 0.931 seconds ahead at the halfway mark.
When the Americans lost one rider and drifted to 1.4 seconds down with 1km to go, the British squad had all but wrapped up gold and attention turned to whether they could break the world record for the third time at these Games, which they did by a huge 1.9 seconds.