Retesting of urine samples from the US Open and Davis Cup produced no positive traces of newly-discovered steroid THG.
After the drug was discovered in the summer, the International Tennis Federation decided to rescreen samples taken both in and out of competition.
"All samples have returned negative," an ITF statement read.
At least five athletes and four NFL players have tested positive for THG, including Britain's European 100m champion Dwain Chambers.
Two positive samples for THG were recorded in retesting of
samples from the World Athletic Championships.
However, the International Swimming Federation found no abnormalities after rechecking samples from its world championships.
The IOC has announced plans to retest samples from the
2002 Winter Olympics in Salt Lake City.
~RS~a~RS~Domestic~RS~q~RS~~RS~z~RS~10~RS~){kind=small}
E-mail this to a friend
Printable version
Inside a drugs test