Former world number one Martina Hingis, who retired from tennis in November after testing positive for cocaine, was banned for two years on Friday after an independent tribunal confirmed the doping offence.
The International Tennis Federation said in a statement that the 27-year-old Swiss would also forfeit the ranking points resulting from last year's Wimbledon championships and $129,481 in prize money.
Hingis, a five-times Grand Slam champion, has denied taking cocaine but said in November she had "no desire to spend the next several years of my life reduced to fighting against the doping officials".
The ITF statement said the anti-doping tribunal had ruled after a two-day hearing last month that samples produced by Hingis at Wimbledon last June had tested positive for a metabolite of cocaine.
It rejected the suggestion made on behalf of the player that there were doubts about the identity or integrity of the sample attributed to her.
"The Tribunal also rejected Ms Hingis' 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," it added.
Larry Scott, chief executive of the Women's Tennis Association (WTA), said in a separate statement: "We are saddened by this news as Martina has meant so much to fans the world over and made many positive contributions to the sport."
He added, however, that the WTA Tour fully supported the tribunal.
"We support and will enforce the ruling of this independent tribunal under the Tennis Anti-Doping Program," he said.