Britain's most successful Olympian, Chris Hoy, yesterday announced his retirement from cycling with immediate effect, prompting glowing tributes from leading figures in the sport.
Dave Brailsford, the British Cycling performance director, who oversaw the 37-year-old Scot's transformation from BMX rider to a track sprinter who won six Olympic golds, as an icon.
"I can't speak highly enough of Chris and his career," said Brailsford. "Chris' application, athleticism and dedication are second to none and I've said it many times, but he is a true Olympic champion who embodies all of the Olympic values."
Hoy made his widely expected announcement at Murrayfield stadium in his native Edinburgh.
"I'm officially announcing my retirement from international cycling," he told a press conference. "It's a decision which I didn't take lightly. It's something I thought about hard with the help of my family and my coaches."
Hoy overtook rower Steve Redgrave as Britain's most successful Olympian at last year's Games in London, when he claimed gold medals in the team sprint and the keirin.
He had hoped to continue competing until next year's Commonwealth Games in Glasgow, where the cycling event will be held at the Sir Chris Hoy Velodrome, but said he was no longer capable of competing at the highest level.
"I've got every last inch of energy and effort out of me," he said. "I went to London and was successful, but I didn't realise quite how much London took out of me. To go on for another year would be one year too far. I don't want to turn up just to wave to fans and get a tracksuit.
"I wanted to compete and get a medal for Scotland and because I didn't think I could do that, I wanted someone else to take my place."
Asked to select his career highlight, Hoy singled out his first Olympic gold medal, in the 1km track time-trial in Athens in 2004, and his last, in the keirin at last year's London Games.
"Athens - stepping onto the podium, hearing my name read out and then hearing 'Olympic champion' after it. To me, that was what my career was all about," he said.
"I thought nothing could compare to that, but in London, to end my career with my sixth gold medal in the nature of the keirin, was a really special moment. But I could go on all day. I'm fortunate I've got so many great memories and I've had so much fun. I still feel the same. I'm going to cycle for the rest of my life and encourage others to take up the sport."
The sustained success of British Cycling over the last six years has exasperated and perplexed their rivals, and in the thunder-thighed Hoy, their painstakingly meticulous approach took human form.
Already an immensely motivated competitor, Hoy found in Brailsford a kindred spirit who nourished and encouraged his appetite for finding the "marginal gains" that became the team's obsession.
For Hoy, it meant hour upon hour in the gym and on the velodrome track, the legacy of which he exhibits not just in the medals around his neck, but also the extraordinary girth of his thighs.
He first tasted major international success at the 1999 World Championships, when he claimed silver in the team sprint.
Three years later, in Copenhagen, he became a double world champion, prevailing in the team sprint and taking victory in the individual time-trial by a margin of just one-thousandth of a second. He was to amass nine more world titles in the years that followed.
His exploits in Beijing, streaking to victory at the Laoshan velodrome in the team sprint, the sprint and the keirin to help fire Great Britain to the top of the cycling medals table for the first time in 88 years, earned him a knighthood and he cemented his legacy in London, sharing a trackside embrace with Redgrave after breaking his record.
British sprint sensation Mark Cavendish, who has won 23 Tour de France stages, said Hoy's impact could not be overstated. "He's one of the most professional athletes I've ever seen, one of the nicest men, on and off the bike, that I've ever met," Cavendish said. "What he's done for cycling for this country has been bigger than anybody can even put into words."
With plans afoot to launch his own brand of bicycles, Hoy has already begun to prepare for life after the sport.
If his approach to business is as single-minded as his dedication on the track, the world's bicycle manufacturers are in for a rude awakening.