Joe Horrigan is considered the foremost professional football historian. He also knew Lamar Hunt and writes about the Chiefs founder in his new book, "NFL Century: The One-Hundred-Year Rise of America's Greatest Sports League."

Horrigan recently retired as executive director of the Pro Football Hall of Fame. He joins Haley on the phone from his home in Canton, Ohio.

https://www.penguinrandomhouse.com/books/592291/nfl-century-by-joe-horrigan/