Jane Onyanga-Omara, and Josh Peter

USA TODAY

Nike, TAG Heuer and Porsche have suspended their relationships with Maria Sharapova after the tennis star failed a drug test.

Sharapova admitted she failed the test in an announcement at a news conference Monday.

She said the drug Meldonium, which she took for 10 years, was prescribed by a doctor and was not on the banned list until the rules changed on Jan. 1. She said she has a magnesium deficiency and a family history of diabetes. The drug has long been thought to be used by athletes, especially in Eastern Europe and Russia, to boost endurance and help recovery.

The test was done at the Australian Open in January.

In 2010, Sharapova signed a deal with Nike worth $70 million over eight years.

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Nike said it was suspending its relationship with Sharapova while the investigation continued.

In a statement, the sportswear firm said: "We are saddened and surprised by the news about Maria Sharapova. We have decided to suspend our relationship with Maria while the investigation continues. We will continue to monitor the situation."

TAG Heuer said Tuesday that it would not renew her contract.

Tennis star Maria Sharapova admits she failed drug test at Australian Open

In a statement, the watchmaker said: "Maria Sharapova was under contract with TAG Heuer until December 31, 2015. We had been in talks to extend our collaboration. In view of the current situation, the Swiss watch brand has suspended negotiations and has decided not to renew the contract.”

Luxury car-maker Porsche on Tuesday said it postponed planned activities with Sharapova “until further details are released and we can analyze the situation.”

Meldonium is used to treat patients with the heart problems angina and myocardial infarction. A statement from the World Anti-Doping Agency confirmed the drug was added to the banned list this year "because of evidence of its use by athletes with the intention of enhancing performance."

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Sharapova's attorney, John Haggerty, said "a positive drug test could result in a ban of up to four years" from the International Tennis Federation. But he added that "mitigating circumstances can lead to the elimination of a ban altogether. ... We're still determining what we are going to request of them. I've asked them to have a cooperative process."

The International Tennis Federation said Sharapova will be suspended from March 12, pending the determination of the case.

Sharapova, 28, has won five Grand Slam titles, including Wimbledon in 2004, her first Slam title. She ascended to No. 1 in the rankings in 2005 and later achieved a career Grand Slam by winning the U.S. Open in 2006, the Australian Open in 2008 and the French Open in 2012 and 2014.



She has amassed almost $37 million in career earnings, second only to Serena Williams, who has earned more than $75 million. But the Russian has made far more off than court thanks to lucrative endorsement deals.

PHOTOS: Maria Sharapova's career