Bradley Wiggins virtually secured his maiden Tour de France victory after winning the penultimate stage-time trial of the race on Saturday.
Wiggins, who took nearly two minutes from defending champion Cadel Evans when he won the stage nine time-trial over 41.5km, went into the 53.5km race against the clock with a 2min 05sec lead over Sky teammate Chris Froome.
And after a smooth, controlled ride over a course that suited him to perfection, the 32-year-old Englishman increased his advantage on the Kenyan-born Briton, who finished second on the stage at 1min 16sec.
It means Wiggins will go into Sunday's final stage to Paris – which usually does not host a battle for the yellow jersey – with an overall lead of 3:21 on Froome.
Barring catastrophe, the Belgian-born Londoner will become Britain's first yellow jersey champion.
"I don't know what to say. Only one more day to go, and I've won the yellow jersey," said an emotional Wiggins.
Sky team manager Dave Brailsford said: "We made it our objective to win this race within five years with a clean, British rider, and that's what we've done. It might be a surprise to everyone else, but it's not a surprise to us."
Italian Vincenzo Nibali of Liquigas capped a solid performance to cement his third place overall.
He now sits 6:19 behind Wiggins and is certain to finish third in Paris as Jurgen Van den Broeck of Belgium dropped to 10:15 in fourth.
Defending champion Cadel Evans, meanwhile, had another day to forget.
He started the day in sixth place overall at nearly 10 minutes behind Wiggins and finished 52nd at 5:54 to drop one place to seventh overall at 15:51 behind the leader.
Having been upstaged by his younger American teammate Tejay Van Garderen in the mountains, Evans suffered the humiliation of being overtaken by 'TVG' on the stage despite starting three minutes earlier.
Van Garderen is set to finish fifth overall at 11:04 behind Wiggins and has virtually secured the white jersey for the race's best-placed rider aged 25 and under. – Sapa-AFP