Johnson will start Wednesday's game against the Blue Jays, Christopher Smith of MassLive.com reports.
Johnson will continue to fill in for the injured Chris Sale (shoulder), who's expected to miss at least one more start. Johnson struggled in his previous outing against the Yankees, as he surrendered five runs across five innings, although he picked up the win in a high-scoring affair. Upon Sale's return, Johnson should head back to a bullpen role.