Four decades after his peak years, McEnroe remains the most famous bad boy of tennis. The American with an edgy rock star persona and sublime lefty skills was a nightmare for umpires in the way Nick Kyrgios is today. His most famous tantrum occurred at Wimbledon 1981. During his first round against Tom Gullikson, he was furious after umpire Edward James ruled ‘out’ on what seemed like a legitimate ace down the middle. “Excuse me?” a surprised McEnroe first said, before exploding, “You can’t be serious, man, YOU CANNOT BE SERIOUS!” McEnroe went on to win the match as well as the tournament. Ironically, his temper issues made him more famous. Post-career, outbursts became his shtick, earning him offers for lucrative commercials, film cameos and exhibition matches.