Osuna disclosed his situation to reporters on Saturday morning, less than 24 hours after not pitching in a save situation for the Blue Jays. The hard-throwing right-hander did not pitch again Saturday against the Kansas City Royals, although Toronto was not faced with a save situation in the 3-2 loss.
"I really don't know how to explain it. I just feel anxious. I feel like I'm lost a little bit right now," Osuna, who is from Mexico, said through a translator before the game. "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."
After Kansas City scored four runs in the bottom of the ninth inning for a 5-4 victory on Friday night, Toronto manager John Gibbons said that Osuna wasn't feeling well, declining to discuss the matter further.
Osuna said he has never experienced this sensation before during his career. Paddy Steinford, the Blue Jays' mental performance coach who travels with the team, has been working with Osuna to overcome his anxiety.
"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," he said. "But, to be honest, I just don't know."
Osuna, 22, has 19 saves and a 2.48 ERA in 31 appearances this season and is the youngest player in major league history to record 75 saves.
The Associated Press contributed to this report.