Former world number one Martina Hingis has been handed a two-year ban after being found guilty of a doping offence.
The 27-year-old Swiss star was found to have tested positive for cocaine while competing at Wimbledon last year.
The International Tennis Federation has rejected Hingis's appeal and handed out a ban starting on 1 October, 2007.
Hingis, who has since retired from the sport, has also had to forfeit ranking points and prize money from Wimbledon and any subsequent tournaments.
The five-time Grand Slam winner, who returned a positive result from a routine urine sample taken after losing to Laura Granville in the third round of the Championships, had previously insisted she was "100% innocent".
She claimed that her innocence was backed up by a negative result on a hair test, which can show whether or not someone has taken cocaine.
What do you make of Hingis's revelation?
Last November, her agent Mario Widmer told BBC Sport: "She will be fighting this, of course. You can be clear about that."
However, a statement from the ITF said: "Following a two-day hearing in December 2007, an independent anti-doping tribunal found that a sample provided by Ms Hingis on 29 June 2007 at the Wimbledon Championships had tested positive for a metabolite of cocaine.
"The tribunal rejected the suggestion made on behalf of Ms Hingis that there were doubts about the identity and/or integrity of the sample attributed to her.
"The tribunal also rejected Ms Hingis's plea of no (or no significant) fault or negligence, on the basis that no mitigation was possible as it had not been shown how the cocaine entered her system."
Hingis, who spent three years out of the sport before returning in 2006, won 43 WTA singles titles during her career.