The 32-year-old Scot was vying for his second gold in his first competitive action since his heroics in Beijing, where he won three Olympic gold medals, but brushed against Frenchman Kevin Sireau and fell out of the race.

Sireau went on to claim victory, with Britain's Ross Edgar fourth.

 

Sir Chris was expected to add to his tally of victories in the men's keirin - one of the events in which he triumphed at the Laoshan Velodrom.

The Edinburgh cyclist won his opening round before leading fellow Scotsman Edgar into the final with victory in the second round.

But Sir Chris, who only returned to serious training last month when the British squad spent four weeks in Australia, tumbled out of the final while taking on Sireau, who remained upright to take victory.

 

Edgar said: "[Hoy and Sireau] got tangled up a bit.

 

"When you hook your arms that turns the steering, and you can't correct it if the other guy is coming past and takes you with him.

 

"As for me, I had nowhere to go."

 

Both riders' bikes were broken, with Sir Chris smashing the forks and frame, such was the impact of his fall.

 

He reportedly suffered cuts and bruises and is set to miss out of the sprint tomorrow.

The team pursuit quartet were the only Britons to top the podium on day two after three golds were won on day one - Hoy, Jamie Staff and Jason Kenny in the team sprint, Victoria Pendleton in the women's sprint and Lizzie Armitstead in the women's scratch race.

The British team once again demonstrated their superiority over the opposition with a supreme victory which demonstrated their intent ahead of next month's Track World Championships in Pruszkow, Poland.

Ed Clancy, who won gold in the event in Beijing, was joined by Steven Burke, Rob Hayles and Peter Kennaugh and the quartet qualified fastest before another blistering display in the final.

Britain were consistently quicker than Spain, eventually passing their rivals 150 metres from the finish line.

Pendleton, who won sprint gold in Beijing, was fifth in the women's 500 metres time-trial, 0.271secs behind Lisandra Guerra Rodriguez of Cuba, who took gold, while Anna Blyth was ninth.

Blyth then combined with Helen Scott to finish fourth in the women's team sprint after losing out to China in their duel for the bronze medal.

David Daniell finished eighth in the men's one kilometre time-trial, while Alexandra Greenfield failed to finish in the women's points race.