On January 21, 1990, at the Australian Open in Melbourne, American tennis player John McEnroe becomes the first player since 1963 to be disqualified from a Grand Slam tournament for misconduct.

A left-handed serve-and-volleyer with a masterful touch, McEnroe was a dominant force in professional tennis in the early 1980s, winning three Wimbledon and four U.S. Open titles between 1979 and 1984, against such formidable opponents as Bjorn Borg, Jimmy Connors and Ivan Lendl. Over his career, he would win 17 total Grand Slams, including nine in men’s doubles and one in mixed doubles. His Davis Cup record was 41-8 in singles and 18-2 in doubles, and he helped the United States win five Cups. McEnroe’s masterful play was often overshadowed, however, by his explosive temper. Always a fan favorite, McEnroe was dubbed “Superbrat” by the British tabloids at the age of 20 and was famous on the tour for his constant arguments and badmouthing of umpires and linesmen.

At the 1990 Australian Open, the 30-year-old McEnroe was trying to win his first major tournament since the 1984 U.S. Open. On January 21, he took on Sweden’s Mikael Pernfors, a two-time National Collegiate Association of America (NCAA) champion, in the fourth round. McEnroe won the first set easily, but Pernfors lifted the level of his game to win the second set. After the players traded service breaks in the third, McEnroe led 2-1. During the changeover, he stopped in front of a lineswoman he thought had made a bad call, glaring at her while bouncing a ball on his racket. The chair umpire, Gerry Armstrong, gave McEnroe a conduct code violation for unsportsmanlike conduct.

Bigger trouble began in the seventh game of the fourth set, with McEnroe leading overall 6-1, 4-6, 7-5, 2-4. Hitting a forehand wide to go down 15-30, McEnroe threw his racket to the ground, where it bounced on the court’s hard surface. Another wide McEnroe forehand prompted another racket smash, this one cracking the racket’s head. Armstrong called another code violation, for racket abuse, and McEnroe started swearing at him, demanding the intervention of Ken Farrar, the Grand Slam chief of supervisors. Farrar arrived and spoke with McEnroe, whose continued complaints and swears were audible to spectators and TV viewers. With Farrar’s authorization, Armstrong called a third and final code violation: “Default Mr. McEnroe. Game, set, match.” The crowd of 150,000 rose to their feet, booing and chanting their support for McEnroe, as McEnroe himself stood with his hands on his hips, stunned. The last player to be disqualified from a Grand Slam for misconduct had been Willie Alvarez of Spain, in the 1963 French Open, 17 years earlier.

In a press conference following the match, a subdued McEnroe explained that he had misunderstood the rules, and was unaware that the previous year’s four-step process to default had been changed to a new three-step rule: first a warning, then a point penalty, then a default.