Indianapolis Colts owner Jim Irsay has been placed on Injured Reserve with a gnarly illness ... forcing him to back out of an upcoming concert with his band.
The news just came out Tuesday morning ... with Adam Schefter releasing a statement from the Colts on 64-year-old Irsay's condition.
"Jim Irsay is currently being treated for a severe respiratory illness," the team said.
Irsay was slated to hit the stage alongside his "Jim Irsay Band" rock group as part of an exhibit and concert event in Los Angeles on Thursday .