Great Britain's men's team pursuit squad claimed a thrilling Olympic gold in a world record time on the second day of competition at the London 2012 Olympic Velodrome.
Ed Clancy, Geraint Thomas, Peter Kennaugh and Steven Burke clocked three minutes 51.659 seconds to triumph by a supreme margin ahead of arch-rivals Australia. The quartet of Jack Bobridge, Glenn O'Shea, Rohan Dennis and Michael Hepburn finished with silver in 3mins 54.581secs.
The British quartet, who won Track Cycling World Championships gold in Melbourne in April, now have successfully defended the title won by Clancy, Thomas, Bradley Wiggins and Paul Manning in Beijing.
New Zealand's Sam Bewley, Marc Ryan, Jesse Sergent and Aaron Gate claimed bronze in 3:55.952, with Russia's Evgeny Kovalev, Ivan Kovalev, Alexey Markov and Alexander Serov finishing fourth (3:58.282).
After delivering in front of an expectant, partisan crowd, Clancy said: "It just blows your mind. We talked about how good it would be to defend it, the Aussies, the Ashes on wheels and all that.
"Just to make it happen, to put your hands in the air, it felt like everyone here was cheering for us. It was just incredible. The whole way round it was just a wall of noise. It was almost surreal, just bizarre. I don't think we've woken up yet. It feels like a dream."
Britain won April's Track Cycling World Championships in Melbourne for a first rainbow jersey in the event since before Beijing, at the Manchester event in 2008.
Thomas added: "A few of us have had wake up calls and we had a bit of a dip after Beijing, which was expected. A lot of people were saying we weren't going to get back up and Australia were coming up hard, but I think we've all really upped our game."
Great Britain's women advanced as they also claimed a world record in team pursuit qualifying. The World Championship-winning women's squad of Dani King, Laura Trott and Joanna Rowsell clocked three minutes 15.669 seconds to go through to Saturday's first round.
The British trio, who lowered their own best set in April in Melbourne, were set to meet the Canada in what is effectively a semi-final. Canada clocked 3mins 19.816secs to progress in fourth, while second-fastest qualifiers the United States (3:19.406) were set to meet Australia (3:19.719), the third quickest, in the second semi-final.