Fisher will work as the opener Friday against the Diamondbacks, Arden Zwelling of Sportsnet.ca reports.
The righty will work ahead of bulk reliever Eric Lauer. Fisher has appeared in eight games out of the bullpen for Toronto this season, posting a microscopic 0.93 ERA, 0.72 WHIP and 12:1 K:BB across 9.2 innings. Fisher pitched Tuesday and Wednesday this week, and his season high for pitches in a game is 32, so he's unlikely to work more than an inning or two.