Matheson is returning from a broken foot suffered during her comeback from knee surgery.
"The goal is to bring her back during the tournament," Canadian coach John Herdman said Monday, "We know it's an impossible mission for the first game. But we'll get her back at some point. That's the goal.
"We've just got to keep hoping the trajectory's forward. But these things can change in a heartbeat. They can change any day — either progressive or regressive. At this point, everything's positive."
With 166 caps, Matheson is a leader for the Canadian team on and off the field. So Herdman has included her in his 23-woman roster for the 24-team tournament that kicks off June 6.
Teams have until 24 hours before the first game to replace a player due to injury reasons.
The 31-year-old from Oakville, Ont., had the same injury in her left foot in 2010 and now has matching screws in each foot.
"The philosophy remains the same with Diana. If we know we can get her a minute on the pitch, we will," said Herdman.
Matheson watched Canada's 0-0 training match with Nigeria on Monday, walking with a slight limp.