Chris Evert said on Monday she was stunned to hear Maria Sharapova failed a doping test - but not by the fact there is doping in tennis.

In fact, Evert claimed she knew players who doped during her career.

The 18-time Grand Slam champion who retired in 1989, said the use of performance-enhancing drugs in tennis went on during her career - which was before the sport adopted current anti-doping rules - and that it likely goes on in all sports.