The Blue Jays placed Estrada on the MLB 15-day injured list April 5 with a right shoulder impingement, Keegan Matheson of MLB.com reports.
Estrada was originally optioned to Triple-A Buffalo, but the team later discovered a shoulder issue that he suffered while playing in the big leagues, so he'll land on the major-league IL. He'll be eligible to return to action Monday, and when he is ready to return the Blue Jays will likely send him back down to Buffalo.