The team has recalled outfielder Alan Roden from the team's Triple-A affiliate, the Buffalo Bisons.
Santander has also been dealing with inflammation in his left hip over the past couple of weeks.
The veteran slugger signed a five-year deal with the Blue Jays in the offseason worth $92.5 million, but has yet to live up to the money.
This season, he's slashing an awful .179/.273/.577 with just six home runs and 18 RBI through 50 games, despite heating up a bit before landing on the IL.
Santander is coming off a season for the division rival Baltimore Orioles in which he hit 44 home runs, the third-most in all of baseball.
Toronto is currently in the middle of the pack in the American League East division with a 28-28 record, winning six of their last 10 games.
They're 6.5 games back of the New York Yankees for first place heading into their matchup on Friday night against the Athletics.