Sven Hans Fredrik "Fidde" Rosengren (born 31 January 1960) is a Swedish professional tennis coach. Biography. Rosengren began his coaching career in 1988 as the coach of Jan Gunnarsson and in 1989 Gunnarsson reached the semifinals of the Australian Open. His coaching time with Gunnarsson lasted until 1992, but in 1990 he also started working with Jonas Björkman. During the time he coached Björkman, Björkman reached the 4th position on the ATP ranking in singles as well as 3rd on the doubles rankings.
https://en.wikipedia.org/wiki/Fredrik_Rosengren