(CNN) -- Lance Armstrong returned to the Tour de France for first time in four years by finishing 10th in the opening time trial in Monaco which was won by Fabian Cancellara of Switzerland.
Armstrong powers past the famous casino at Monte Carlo on the first stage.
Cancellara, renowned for his awesome performances against the clock, clocked 19 minutes 32.14 seconds for the 15.5 kilometer course in the Mediterranean principality.
Armstrong's Astana teammate and Tour favorite Alberto Contador finished in second place at 18 seconds with Britain's Bradley Wiggins in third.
Seven-time Tour champion Armstrong was the 18th of the starters in the 180-strong field and briefly held the lead with a respectable time of 20 minutes 12.36 seconds which eventually left him 40 seconds adrift of Saxo Bank powerhouse Cancellara.
The 37-year-old Texan looked strong on the initial climbs which took the riders high above Monte Carlo before descending to the finish with a series of technical turns at high speed.
Germany's Tony Martin from Team Columbia-High Road and another Astana rider Levi Leipheimer quickly bettered his time, but Armstrong was satisfied with his performance.
"It felt pretty good," he told Eurosport. "I didn't have an big illusions, I didn't expect to win and take the (yellow) jersey, but relative to the specialists like Levi and Tony Martin it was good," he added.
The opening time trial was expected to give an early indicator of the form of the leading contenders and Astana team leader Contador showed his climbing ability by having the fastest time at the intermediate check point high above Monte Carlo.
But Cancellara's extra power proved the difference in the closing kilometers as he set an unassailable time.
He caught Giro d'IItalia winner and Tour contender Denis Menchov for a minute to claim the first yellow jersey of the 96th edition of cycling's most famous race.
For Menchov it was valuable time lost, while of the other favorites Cadel Evans of Australia rode strongly to claim fifth on the stage, but only five seconds adrift of Contador.
Defending champion Carlos Sastre of Spain finished one minute and six seconds behind Cancellera.
As expected, Astana look to have a strong hand with Armstrong rounding out four of their team in the top 10, with Andreas Kloeden in fourth and Leipheimer sixth.
After Saturday's race against the clock, the next big test for riders with pretensions to be wearing the yellow jersey in Paris in three weeks time comes in the Pyrenees on stage seven.
Armstrong, who won a record seven straight Tours from 1999-2005, announced his return to cycling last year, saying he wanted to publicize his cancer charities.