Injured Canada captain Christine Sinclair, who holds the record for most international goals with 186, is among seven national team players unavailable for next week's SheBelieves Cup in Orlando, Canada Soccer said on Saturday.
Canada Soccer also said that "despite a concerted effort" Lyon defender Kadeisha Buchanan and forward Jordyn Huitema and defender Ashley Lawrence, both of Paris Saint-Germain, were denied releases by their French clubs.
"Given the new roster realities, what a great opportunity for players to rise up and show that they can compete at this Olympic level," Canada head coach Bev Priestman said in a news release.
"The tournament will be used to assess the player pool and players' readiness to achieve our goals at the Olympic Games."
The USWNT have also been hit with a number of injuries. Manchester United's Tobin Heath has been ruled out until March at the earliest while Manchester City manager Gareth Taylor said on Friday that it was "highly unlikely" Sam Mewis would travel after picking up an injury in the national side's January camp.
Canada and the USWNT meet on the first day of the tournament on Feb. 18.