There is what was, and there is what might have been.
There is the stirring memory of what Gale Sayers did as a running back for the Bears, and there is the unshakeable belief that he would have done so much more if not for the shortcomings of the human knee.
Here one moment on the football field, and gone the next. The Kansas Comet indeed.
Sayers died Wednesday at 77 after dealing with dementia for years. He will be remembered most for a brilliant afternoon in which he tied an NFL record with six touchdowns in a game, and he will be remembered for injuries that robbed him of his speed and agility.