Manti Te'o -- the college football superstar who fell for one of the most famous catfishing scams to date -- is opening up on his decision to go public with his side of the hoax ... saying attending a Jay-Z concert helped him come forward.
Remember, the former Notre Dame linebacker reportedly lost his grandma and girlfriend within hours of each other in 2012 ... except the entire romance was based on a lie.
As it turns out, Te'o didn't know his GF -- Lennay Kekua, a student at Stanford -- didn't actually exist .