Kay is slated to start Tuesday's game against the Athletics in Oakland, Arden Zwelling of Sportsnet.ca reports.
After being called up from the alternate site Sunday, Kay was available out of the bullpen for Toronto's series finale versus Atlanta, but he wasn't needed in the 7-2 victory. He'll now step into the rotation to eat innings as the Blue Jays' No. 5 starter, but Kay may just be keeping a seat warm for Nate Pearson (groin), who is in the process of ramping up for starting duties in the minor leagues after spending the first month of the season on the injured list.