Björn Borg was born in Stockholm on 6 June 1956 and grew up in nearby Södertälje. He started with a two-handed grip on both sides, and although he later hit his forehand with one hand, he kept the two-handed backhand against the advice of the day, when few believed a man could win at the top with it. By 13 he was beating the best Swedish players under 18, and Sweden's Davis Cup captain Lennart Bergelin warned against anyone trying to change his rough-looking, jerky strokes.
Bergelin picked him for the Davis Cup team in 1972, when Borg was 15, and stayed his coach and closest confidant for the rest of his career. The results came early: the Italian Open at 17 and the French Open at 18, beating Manuel Orantes in five sets to become the youngest winner in Paris at the time. In 1975 he helped Sweden win the Davis Cup for the first time, by then with 19 Davis Cup singles wins in a row.
In 1976 he won Wimbledon without dropping a set, the first of five titles in a row there, and in August 1977 he became world No. 1. From 1978 to 1980 he won the French Open and Wimbledon in the same year three times running, a double that asks a player to switch from slow clay to fast grass within weeks. His fifth Wimbledon, in 1980, came after a five-set final against John McEnroe that is still counted among the best ever played. In all he won six French Opens, five Wimbledons and 66 singles titles, and he won 89.8 per cent of his matches at the majors, with 14 consecutive wins in major semifinals.
Two majors never came: he did not win the US Open or the Australian Open. In 1981 he lost the Wimbledon and US Open finals to McEnroe, and in January 1983, aged 26, he announced his retirement, a decision that shocked the sport. A comeback between 1991 and 1993 brought no success. Off court he founded a sportswear company in the early 1990s, and he was inducted into the International Tennis Hall of Fame in 1987.