The Ligue 1 side face the New York Red Bulls on Tuesday following last week's 0-0 draw with MKS Pogon, and Garde is predicting a tough encounter.
"The spirit in the squad has been good since the start of pre-season training," Ligue1.com quotes Garde as saying. "On Tuesday we will play our second friendly match and it will be very hard.
"The New York Red Bulls will be a very tough opponent, a side I think are good enough to play in Ligue 1, without necessarily fighting for the title. It will be a solid match, a very good test for us."
Lyon finished third in last season's Ligue 1.