Armstrong, the leader of the United States Postal Service team, opened the 91st Tour de France here Saturday by finishing second in the short prologue to three weeks of racing, leaving all his major rivals behind.
It was a strong psychological blow by Armstrong, who is seeking a record sixth consecutive victory in the Tour. His performance may go far in dissipating the feeling that his powers are on the wane, as some of his results this spring hinted.
The race, over 3.8 miles on flat streets in the center of Liège and along the Meuse River, was won by Fabian Cancellara, a 23-year-old from Switzerland who rides for the Italian team Fassa Bortolo.
A specialist in prologues and twice, in 1998 and 1999, the junior world champion in the time trial, Cancellara was clocked in 6 minutes 50 seconds, a speed of 33.2 miles an hour.
Armstrong was two seconds slower than Cancellara, who donned the leader's yellow jersey but does not rate as a contender in the Tour.
"I'm satisfied by the way I felt, but I'm disappointed to lose by only a couple of seconds," Armstrong said, according to The Associated Press, after a congratulatory kiss from his companion, the musician Sheryl Crow. "That's the way it goes. The most important thing is, how does it feel? I was very comfortable, I felt strong, and that feels good."
Third in the individual race against the clock was José Gutierrez, a Spaniard with the Illes Balears team from his homeland, eight seconds behind Cancellara. The Australian Brad McGee, with fdjeux.com and the winner of the prologue in the last Tour, was fourth, nine seconds behind. Thor Hushovd, a Norwegian with Crédit Agricole, was fifth, 10 seconds behind. Two other Americans finished in the top 10: Bobby Julich, who rides for CSC from Denmark, was ninth, 12 seconds behind; and George Hincapie, Armstrong's teammate, was 10th, also 12 seconds behind. Levi Leipheimer, the American leader of the Rabobank team from the Netherlands, was 13th, 15 seconds behind the winner.
Three riders considered among Armstrong's top rivals finished at least 15 seconds slower than he did. Jan Ullrich, the leader of T-Mobile from Germany and the second-place finisher in the last Tour and in four others, was 16th Saturday by 15 seconds; Tyler Hamilton, the leader of the Phonak team from Switzerland, who was fourth last year and 18th Saturday, 16 seconds behind Armstrong; and Iban Mayo, the leader of the Euskaltel team from his homeland, Spain, sixth last year and 26th Saturday, 19 seconds behind Armstrong.
With three weeks to go and many mountains ahead, those deficits are not damaging, except to the morale. Mostly they served as a warning that Armstrong is starting the Tour at the top of his game.
"It's just a start," Armstrong said, according to The A.P. "They don't call it the prologue for nothing. It sets the tone of the race for the first week. There is a lot of dangerous racing to go. Just in three days, we have some sections of cobblestones, that if it rains and is windy, will be very dangerous."
A huge crowd watched the prologue in cool and windy weather with occasional sprinkles. The turnout was surprising because of a lack of the usual hoopla to welcome a Tour de France. There were few signs and banners in and around Liège and only the rare store window was decorated with a bicycle motif, in contrast to the standard celebration in a start city.