John Patrick McEnroe, Jr. (born February 16, 1959) is an American former World No. 1 professional tennis player. McEnroe won seven Grand Slam singles titles three at Wimbledon and four at the US Open nine Grand Slam men's doubles titles, and one Grand Slam mixed doubles title. He is remembered for his shot-making artistry and superb volleying; for his famous rivalries with Björn Borg, Jimmy Connors and Ivan Lendl; for his confrontational on-court behavior, which frequently landed him in trouble with umpires and tennis authorities; and for the catchphrase "You can not be serious!" directed toward an umpire during a match at Wimbledon in 1981. He was inducted into the International Tennis Hall of Fame in 1999. McEnroe is also the older brother of Patrick McEnroe, who is also a former professional tennis player and the present Captain of the United States Davis Cup team, a position that John served in previously. They also both are now often commentators for Grand Slam television coverage in the United States.