15. Tiger Woods
Woods enjoyed phenomenal success in the 2000s before his sordid sex scandal. The golfer was one of the most clean-cut sports heroes but it instantly changed. After a drunken crash, dozens of women accused him of extramarital affairs.

This ruined Woods’ marriage and his career. He entered rehab and had several years in the wilderness because of injury. There was a time when he was clearly on track to be the greatest ever (via People).