Peyton Manning had multiple neck surgeries and missed all of 2011 before returning to the field with the Denver Broncos in 2012. He promptly earned a 12th Pro Bowl selection after throwing for 4,659 yards and the second-most touchdowns of his NFL career (37).

Manning accomplished all of that without being 100 percent recovered from those neck surgeries.

"You know, I still have certain challenges," Manning told WATE-TV on Friday while visiting the University of Tennessee campus for an event. "When you're dealing with nerves, I've learned it's a patience deal. They kind of say it could be a year or two, or it may never come back, so I'm kind of hopeful. I kind of wish certain things would come back a little bit more, but I have learned to adjust and compensate in the state that I am. I still would like to make some more improvement. I still work at it.