Stevenson shocked the tennis world in 1999 when, in her first appearance at Wimbledon, she became the first woman qualifier in the Open Era to reach the semi-finals. In the fourth round, she saved one match point against Lisa Raymond in a 2-6, 7-6, 6-1 win. She then beat Jelena Dokic in three sets in the quarter-finals, before finally being knocked-out in straight sets by the eventual-champion Lindsay Davenport. Stevenson joined Chris Evert and Anna Kournikova as the only women in recent times to reach the semi-finals on their Wimbledon debut.

Since her dramatic first year as a professional in 1999, 2002 has been Stevenson's most successful year on the tour. She finished runner-up in two top-level touranments that year in Memphis and Linz. And she also won one tour doubles title at Leipzig, partnering Serena Williams.

Since 2002, Stevenson has been hampered by injuries and has struggled to find her form. An extensive labral tear in her right shoulder sustained in January 2003 required surgery. This was done on September 21, 2004.

As a junior player, Stevenson won the US Open girls' doubles title in 1997. She was ranked the No. 5 junior in the US in 1996.

Stevenson has been coached by her mother, Samantha Stevenson. The identity of her father was not publicly known at the time she became professional in 1999, but it was soon revealed that her father was former NBA star Julius Erving. The pair had a relationship in 1980, when Stevenson was a sports writer in Philadelphia and Erving was playing for the Philadelphia 76ers.

Grand Slam performance timeline (singles) Tournament 2006 2005 2004 2003 2002 2001 2000 1999 1998 Australian Open - 1r 2r 1r 2r 1r - - French Open - - 1r 1r 1r 1r - - Wimbledon - - 1r 1r 2r 2r SF - U.S. Open 1r 1r 1r 1r 1r 1r 1r 1r