Espinal left Wednesday's game against the Philadelphia Phillies due to discomfort with his left side.
The 27-year-old Espinal, who was selected to his first All-Star Game this season, is hitting .267/.322/.370 this season with seven home runs and 51 RBI.
Toronto also recalled infielder Otto Lopez from triple-A Buffalo.
Lopez has a .297/.378/.415 slash line plus three homers and 34 RBI in 91 games with the Buffalo Bisons this year. He has also appeared in three game with the Blue Jays as a defensive replacement/pinch runner.
The Blue Jays (84-65) begin a pivotal series Thursday night against the Tampa Bay Rays with a two-game advantage on their division rival for the top wild card spot. Watch live on Sportsnet and SN NOW.