Merryweather suffered a left oblique strain Tuesday, Arden Zwelling of Sportsnet.ca reports.
The 28-year-old was never a likely candidate to be included on the Blue Jays' season-opening roster, and the timing of the injury likely means he won't be ready for the start of the season. Merryweather has yet to make his major-league debut and is expected to serve as an emergency depth option once healthy.