25 examples of Peyton Manning's insane competitiveness

On Sunday, Peyton Manning will lead the Denver Broncos in what may be his last shot at winning a second Super Bowl.

Win or lose, Manning will be remembered as one of the greatest quarterbacks in NFL history. Despite his easygoing persona, Manning reached his level of greatness by being incredibly competitive both on and off the field.

The intense anecdotes below include what he went through to keep playing after neck surgery, his sneaky first-quarterbacks meeting in college, and his crazy work ethic in high school.