Who won more singles titles, Steffi Graf or Heinz Günthardt?
Steffi Graf: Stefanie Maria "Steffi" Graf (] ; born 14 June 1969) is a German former tennis player, who was ranked world No. 1 during her career. Heinz Günthardt: Heinz Peter Günthardt (born 8 February 1959 in Zürich) is a former tennis player from Switzerland, who won five singles titles during his professional career, including the Rotterdam WCT in 1980.
i don't know