Ryu made a rehab start for the Triple-A Buffalo Bisons last Saturday, giving up five runs (two earned) in four innings while striking out six and walking none.
The South Korean made just two starts with Toronto before landing on the injured list this season, posting a 13.50 ERA while pitching only 7.1 innings.
Ryu's problems date back to last season, when he struggled during the team's playoff push, not making it to the sixth inning in any of his final four starts.
Kevin Gausman will start Friday's series opener, with Alex Manoah slated for Sunday's finale.
The Blue Jays (17-15) have lost four in a row and are third in the American League East, two games back of the second-place Rays.
Watch Friday's series opener at 7:10 p.m. ET / 4:10 p.m. PT on Sportsnet ONE or SN NOW.