Are Danie Visser and Bob Bryan both professional tennis players?
Danie Visser Danie Visser (born 26 July 1961) is a former professional tennis player from South Africa. A doubles specialist, he won 3 Grand Slam men's doubles titles (2 Australian Open and 1 US Open). Visser reached the World No. 1 doubles ranking in January 1990.
Robert Lansdorp Robert Lansdorp (born 1938, Semarang, Indonesia) is a professional tennis coach. He first rose to international fame in 1979 when his student Tracy Austin became the youngest US Open Women's Singles champion in history at age 16. He has gone on to coach other tennis champions including Pete Sampras, Lindsay Davenport, and Maria Sharapova. He is regarded as an expert on groundstrokes, in particular the forehand, advocating a powerful, flat hitting technique commonly referred to as the "Lansdorp Forehand".