Muhammad Ali during his first reign as champ, 43 years ago

Former President George W. Bush was happily stunned when legendary former heavyweight boxing champ Muhammad Ali stood facing him.

Bush was at a Barnes & Noble Booksellers store in Phoenix today signing his book, Decision Points when the Greatest entered (with the Secret Service) to shake hands.

With his famous comic humor, Ali sat next to Bush and held the book up as press and public snapped photos.