Bradley Wiggins was overcome with emotion after moving on to the verge of achieving a lifelong goal of victory in the Tour de France.
The 32-year-old triple Olympic champion enhanced his position at the top of the general classification with an imperious performance in the 53.5-kilometre stage-19 time-trial from Bonneval to Chartres, which saw him move three minutes 21 seconds clear of Team Sky colleague Chris Froome, with Vincenzo Nibali (Liquigas-Cannondale) 6mins 19secs behind in third.
Barring a freak accident on tomorrow's concluding 120km 20th stage from Rambouillet to the Champs-Elysees in Paris, Wiggins is set become the first British winner of the fabled yellow jersey in the 99th edition of the legendary race.
Wiggins finished fourth in the Tour in 2009 - equalling Robert Millar's 1984 British best - and crashed out with a broken collarbone when among the favourites in 2011.
As well as the scientific approach of Team Sky, who, led by Dave Brailsford, are now set to achieve their goal of winning the Tour with a British rider within five years, perspective has helped Wiggins to his greatest sporting achievement.
"I've got a lot of other things in my life that mean more to me than this and I'd give it up tomorrow for that," Wiggins said.
"But in a sporting sense it's my greatest sporting achievement. I've just won the Tour. What else is there bigger than that?
"It's probably the bonheur (happiest moment) of my sporting career, perhaps not in life."
In the final stages of a route to Chartres which featured a litany of Union Flags, with Britons flocking south west of Paris to witness history, Wiggins recalled the people and the moments which brought him to this point.
"The last 10k I was thinking of a lot of things and it was spurring me to go on even harder," he added.
"Just thinking back to my childhood. My father leaving us when I was a kid and growing up with my mum in a flat.
"My grandfather brought me up; he was my father role-model.
"He died when I was on the Tour two years' ago. When I came home from the Tour in 2010 I had to go to his funeral.
"Going back as a child, watching the Tour de France as a kid on telly, from the age of 10, 11, 12, all through the (five-time winner Miguel) Indurain years.
"Dreaming that one day you would win the Tour, but thinking: 'What chance has a kid growing up in central London got of winning the Tour?'
"It's been an incredible road, since I was junior world champion in '98 and being in that British set-up with Dave Brailsford and Shane (Sutton).
"They've seen me not only grow as a teenager, but go through everything, to today, where I've won the Tour, barring tomorrow."
The final day will be Wiggins' 13th in succession in the race leader's yellow jersey on a Tour he has previously described as a goldfish bowl.
He added: "The thing I kept reminding myself the last three weeks, which has given me perspective and kept me in reality, is the fact that it is only sport. It's not life and death. It would be very easy in the Tour to lose that sense of reality."
Wiggins has been in stunning form all season, winning the Paris-Nice, Tour de Romandie and Criterium du Dauphine stage races and proved his ability once more today.
He is not fully aware of the impact his win is set to have, other than some interaction through Twitter.
"What sometimes happens in sport it goes beyond sport and other people start paying attention," he said.
"I even had a direct message from (footballer) Joey Barton. He particularly liked me swearing.
"I'm determined to not let it change me. I'm not into celebrity life, red carpet, all that rubbish.
"I go home and I have to clean up dog muck and that's incredibly grounding."
The margin of Wiggins' victory answered many of those who questioned why Froome, who appeared marginally stronger in the mountains, was not Team Sky's Tour leader.
Wiggins and Froome - set to become the second Briton on the Tour podium - had lunch together this afternoon and Wiggins dismissed suggestions of disharmony after Froome's attack on stage 11 to La Toussuire, which exposed a weakness in the Team Sky leader.
"There is no issue, there is no problem," Wiggins said.
"The reason we have been good these three weeks is because of what we've done as a team. That's the reason we're in this position now.
"Next year it could be Chris (in the yellow jersey)."
The collective strength of Team Sky has helped to propel Wiggins to glory and they were often seen riding at high tempo in the mountains, limiting the prospect of attacks.
"I think the Tour is a lot more human now," said Wiggins, who will be seeking to help Mark Cavendish to victory tomorrow in Paris.