Jens Voigt, of the CSC team, won Sunday's four-kilometre prologue stage of the high-profile Paris-Nice race.
Voigt was 27 seconds quicker than Armstrong
The German clocked a time of five minutes and 15 seconds to edge out Swiss cyclist Fabian Cancellara and Dutchman Erik Dekker.
Six-times Tour de France winner Lance Armstrong was 140th, 27 seconds behind.
Armstrong has said he will race in Dauphine Criterium in the French Alps from 5-12 June rather than the Tour of Switzerland this summer.
The Texan also said there is a small chance he would take part in April's grueling Paris-Roubaix race, but he is leaving the decision to his Discovery Channel team director Johan Bruyneel.
The Paris-Nice, which finishes next Sunday, is the first race on the new UCI ProTour programme and also Armstrong's first big event at the head of his new Discovery Channel team.
Between now and October, the 20 teams will race another 26 events, including the Tour de France.
Paris-Nice prologue results:
1. Jens Voigt (Ger) CSC 5:15
2. Fabian Cancellara (Sui) at 02
3. Erik Dekker (Ned) 03
4. Vladimir Gusev (Rus) 03
5. Sylvain Chavanel (Fra) 04
6. Nico Mattan (Bel) 04
7. Alberto Contador (Spa) 04
8. David Zabriskie (USA) 05
9. Oscar Pereiro (ESP) 06
10. Michael Rogers (AUS) 06