"What I said: A source I consider reliable told me he is out for the season. I do believe that the actual diagnosis is still being determined."
So, even though anything has yet to be confirmed, it's still quite possible that this could happen to Manning.
After undergoing two neck surgeries in the past 15 months, it's not out of the question that he could be out for the season.
With that in mind, if Manning is in fact out for the season, here are five Colts players who need to learn to play without him.