Cal Ripken Jr. has made headlines this month by showing at least some level of interest in becoming a big league manager. But whether the Orioles legend would be successful in that role is far from a given. Frank Robinson became a Manager of the Year after his Hall of Fame playing career, and Celtics great Larry Bird took the Indiana Pacers to an NBA Finals as a coach. But they're more the exception than the rule. For today's "Throwback Thursday" we look at eight greats who struggled when they hung up their gear and took over as a coach/manager.