Sven Lennart Bergelin (10 June 1925 – 4 November 2008) was a Swedish tennis player and coach.

Bergelin is best known for his work with Björn Borg, whom he trained between 1971 and 1983, helping him to win 11 Grand Slam tournaments.

Between 1971 and 1976, Bergelin captained the Swedish DC team and in 1975 he led them to victory as they defeated Czechoslovakia in the finals.

During this period helped Borg become the first player in the Open Era to win three majors without dropping a set.

According to Peter Bengtsson, a spokesman for the Swedish Tennis Association, he died from heart failure at a Stockholm hospital.