Hirschfeld took the afternoon off to nurse a sore back aggravated on the flight over from Norway where he plays club football.
"No issues with Lars at all. Just precautionary," said interim coach Colin Miller
Fresenga, meanwhile, got a clean bill of health from a doctor.
"He's good to go as well," added Miller.
Fresenga is slated to join the Vancouver Whitecaps training camp after his international commitments.
A young Canadian squad is preparing for friendlies against Denmark in Tucson, Ariz., and the United States in Houston.
Miller ran two-a-day practices Monday and Tuesday.