Claim: Steffi Graf is a professional tennis player.
Evidence: Graf was ranked world No. 1 by the Women 's Tennis Association -LRB- WTA -RRB- for a record 377 total weeks -- the longest period for which any player , male or female , has held the number-one ranking since the WTA and the Association of Tennis Professionals began issuing rankings.
The Association of Tennis Professionals -LRB- ATP -RRB- was formed in September 1972 by Donald Dell , Bob Briner , Jack Kramer , and Cliff Drysdale to protect the interests of male professional tennis players.
Stefanie Maria `` Steffi '' Graf -LRB- -LSB- ˈʃtɛfiː ˈgʁa : f -RSB- ; born 14 June 1969 -RRB- is a German former tennis player , who was ranked world No. 1 during her career.