, the former Oregon track star, is considered the world's greatest athlete after twice winning Olympic gold medals in the decathlon.
But is he ninja?
Fans will find out on Thursday night, when Eaton and eight others, stars of television, sports and movies, will compete in the first celebrity edition of "American Ninja Warriors."
You know the sports entertainment show -- competitors navigate the insanely challenging obstacle course in a quest to earn the title of American Ninja Warrior.
In the celebrity version, each star is paired with an elite ninja who help them prepare for the physically taxing event and then coach and cheer them through the obstacles.