Osuna told reporters he is unsure when he will be available to pitch again as he tries to work through his issues. He did not pitch in a save situation for the Blue Jays on Friday night against the Kansas City Royals.
"I really don't know how to explain it. I just feel anxious. I feel like I'm lost a little bit right now," the hard-throwing right-hander, who is from Mexico, said through a translator. "I'm just a little bit lost right now.
"This has nothing to do with me being on the field. I feel great out there. It's just when I'm out of baseball, when I'm not on the field, that I feel just weird and a little bit lost."
The 22-year-old Osuna has 19 saves and a 2.48 ERA in 31 appearances over 29 innings this season.
Osuna's absence was noticeable Friday night as the Royals rallied to score four runs in the bottom of the ninth inning for a 5-4 victory. Blue Jays manager John Gibbons would only say after the game that Osuna was unavailable because he wasn't feeling well enough to pitch.
Osuna made it clear Saturday that his problem was not physical.
"I wish I knew how to get out of this, but we're working on it, trying to find ways to see what can make me feel better," Osuna said. "But, to be honest, I just don't know."