Deduno left in the second inning of his start against the Yankees on Wednesday because of an irritated left eye. The right-hander threw 1 2/3 scoreless innings with no hits and two strikeouts before leaving, but he also issued two walks.
"We saw it when he was out there the other day -- he wants to pitch. We all know that," manager Ron Gardenhire said. "But we can't have a guy out there on the mound who can't see the ball and has blurry vision."
Deduno is 6-5 with a 4.44 ERA over in 15 starts (79 innings) this season.
Minnesota could go with either right-hander Anthony Swarzak or lefty Brian Duensing to start Tuesday's game in Toronto. Both long relievers have struggled in spot starts this season, with Swarzak going 0-4 with an 8.35 ERA in four starts, while Duensing is 2-8 with a 6.92 ERA in 11.
"[We'll] do our research [on] both of those guys," Gardenhire said. "We'll figure out which one we go to."
Jordan Garretson is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.