FRANKFURT (Reuters) -- Porsche said it would suspend tennis player Maria Sharapova as its brand ambassador in light of her admission that she failed a doping test.
The Russian tennis star on Monday admitted she had failed a drug test at the Australian Open due to a substance she was taking for health issues.
"We regret the current news about Maria Sharapova. Until further details emerge and we are able to analyse the situation, we have decided to suspend planned activities," Porsche said in a statement.
Sharapova signed her three-year deal with Porsche in April 2013.
She earned $29.7 million last year, Forbes magazine reported, and most of it came from endorsements, appearances and royalties rather than her victories on court. She was world's highest-paid female athlete last year for the 11th consecutive year, and Forbes put her off-court career earnings at more than $200 million.
"We're now entering a zero tolerance era for sponsors," said Rupert Pratt, co-founder of sports sponsorship agency Generate. "It is now seen as not acceptable to 'stand by your man' because of the amount of scrutiny corporates are now under."
Sharapova, who lit up women's tennis when she won Wimbledon in 2004 as a 17-year-old and is still ranked among the top players, said on Monday she tested positive for meldonium, which is used to treat diabetes and low magnesium.
She said she had been taking the substance for a decade for health reasons and had not read an e-mail informing her that a ban on its use in sport, imposed by the World Anti-Doping Agency, had come into force on Jan. 1.
She will be provisionally suspended from playing tennis from March 12 and could be prevented from competing for Russia at the Rio de Janeiro Olympics this year.