John Patrick McEnroe Jr. is an American former professional tennis player. He was ranked as the world No. 1 in men's singles by the Association of Tennis Professionals (ATP) for 170 weeks, and as world No. 1 in men's doubles for 269 weeks (third-most of all time). He is one of two male players (alongside Stefan Edberg) to have held both No. 1 rankings, and the only one to hold both simultaneously. McEnroe was best known during his playing career for his shot-making and volleying skills, his rivalries with Björn Borg and Jimmy Connors, and his confrontational on-court behavior, which frequently landed him in trouble with umpires and tennis authorities.
McEnroe won an Open Era record 155 career titles: 77 in singles, 77 in doubles and 1 in mixed doubles. This includes seven singles majors (four at the US Open and three at Wimbledon), nine men's doubles majors, and one mixed doubles major. McEnroe is the only male player to win more than 70 titles in both singles and doubles. His singles match record of 82–3 in 1984 remains the best single-season win rate of the Open Era.