From Champ to Chump in a Progressive Minute

Roger Federer has won more Grand Slam tennis titles than any other man in history. He has spent more weeks as the number one ranked player in the world than anyone else, including 237 consecutive weeks at one stage (that’s four-and-a-half years, for the arithmetically challenged). By any standard, he merits the unqualified epithet “Champion.” Or rather, he did. Today, he is just...