Britain's four-time Olympic gold medallist Chris Hoy has been told he won't defend his individual sprint title at the London Games.
British Cycling chiefs on Thursday informed Hoy that he will compete in the men's Keirin and team sprint, while Grean Britain team-mate Jason Kenny will contest the individual sprint.
At the Beijing Games in 2008, Hoy, who won his first gold in Athens in 2004, became the first Briton to land three gold medals in a single Olympics since Henry Taylor in 1908.
But British cycling performance director Dave Brailsford has elected to select Kenny for the individual event after he finished in second place ahead of the 36-year-old Scot at the World Championships in Melbourne earlier this year.
"We have now finalised our selection for the track events and in particular we have made the decision over who will ride the sprint," Brailsford said.
"Both Chris and Jason are on great form and that made it a difficult choice, but we have decided to select Jason to contest the sprint and Chris will concentrate on the keirin. We believe this gives us the strongest team possible going into the Games."
Hoy and Kenny will both compete in the men's team sprint alongside Philip Hindes and reserve Ross Edgar.
Hoy refused to criticise the decision and backed Kenny to make a big impact in his place.
"Whilst I'm obviously disappointed not to be defending all three of my 2008 Olympic titles in London, Jason thoroughly deserves this opportunity and has a great chance of success in the sprint," Hoy said.
"I am now focused entirely on the keirin and team sprint and my goals for those two events haven't changed."