The 31-year-old Swiss rider proved he's positively dominant in time-trials over the 6.4-kilometre (4-mile) race against the clock in Liege. This time, Cancellara outclassed another Tour title favourite: Bradley Wiggins, who is aiming to be the first Briton to win. He was second, seven seconds behind.
Cadel Evans embarked on his title defence in a solid form, finishing 13th — but importantly, 10 seconds behind Wiggins, who many see as the main threat to the Australian's hopes of a repeat. Cancellara is unquestionably the world's best time-trial rider, but isn't considered a Tour contender because he often struggles in the mountains.
"What a great opening — again!" Cancellara said. "I did the most I could. It's not always easy. I always do the maximum ... It's a great feeling and this certainly takes some of the pressure off."
The Tour start offered a welcome return to racing — the entree into three weeks and 3,500 kilometres of criss-crossing France, nosing into Switzerland, and scaling climbs in the Alps and Pyrenees before the July 22 finish on Paris' Champs-Elysees. Two other individual time-trials await.
RadioShack, built on the remains of teams that Armstrong led to a record seven Tour victories, has faced a rough patch. Its current leader, Andy Schleck, is staying home to nurse a spinal injury he sustained in a crash in the Criterium du Dauphine this month; team manager Johan Bruyneel — Armstrong's longtime mentor — is staying away to avoid being a distraction as he, Armstrong and others are targeted by a U.S. anti-doping case.
In a further embarrassment, Enrico Carpani, a spokesman for cycling governing body UCI, said it received information from several RadioShack riders that they'd faced delays in receiving some salary payments. Team spokesman Philippe Maertens said he believed they had been paid, "and if not, there is a reason for it." He called it a "private issue."
Brushing aside the team's issues, Cancellara said he was focusing "on what I have to do — and that's riding my bike." He said the victory, which he dedicated to his pregnant wife, was doubly rewarding because he broke his collarbone in the Tour of Flanders in April and wasn't sure he'd be at his best for the Tour prologue.
Cancellara has now earned the leader's yellow jersey for 22 days in his career, equaling the marks of other Tour greats including two-time winner Laurent Fignon of France, American triple champion Greg Lemond and Dutchman Joop Zoetemelk. All of Cancellara's prologue victories have been outside France: He beat Armstrong by two seconds in Liege in 2004, and also won in London in 2007, Monaco in 2009, and Rotterdam in 2010.
Wiggins, a three-time Olympic champion, said he believed going into the prologue that "there was a man who could beat me: There is always Fabian, he is the best in the world" when it comes to time trials.
"I finished second, so that's a good thing," added Wiggins. "Physically I felt fantastic. I didn't take any major risk because there were a lot of tricky sections."
Evans, too, said he'd expected to be outclassed in the prologue, and put his ride into a broader perspective.
"Not good, but not bad," the Australian said. "Of course I'd rather concede less seconds, you never want to lose time ... I've got one (general classification) rider ahead of me, but I was kind of half-expecting that. Wiggins, what his background is, is these short efforts."
"For me the real racing starts tomorrow," Evans added. "I'm just happy to get it going, and looking forward to some good racing. ... It's like 6 kilometres out of 3,500 or so, so in that regard it's a small comparison."
His American team, BMC, had some bright spots. Tejay van Garderen, a 23-year-old American, placed fourth — 10 seconds behind Cancellara — and earned the white jersey of the best young Tour rider. Near the other end of the cycling career lifespan, 39-year-old compatriot George Hincapie began his 17th Tour — setting a new record. He finished 22nd.
Sunday's first stage takes riders over a mostly flat, 198-kilometre loop from Liege to the nearby town of Seraing.___
Eds: Greg Keller and Samuel Petrequin contributed from Liege.