Former world number one Maria Sharapova has exposed she failed a drug test at the Australian Open. The Russian, 28, tested positive for meldonium(米屈肼), a substance she has been taking since 2006 for health issues. The International Tennis Federation(ITF) said the five-time Grand Slam champion would be temporarily suspended from March 12. Sportswear company Nike said it was cutting its relationship with her until the investigation was complete.

   "I did fail the test and take full responsibility for it," said Sharapova, who won Wimbledon as a 17-year-old in 2004.

   Sharapova, who lives in Florida, was charged on March 2．"It is very important for you to understand that, for 10 years, this medicine was not on Wada's banned list and I had been legally taking that medicine for the past 10 years," she said. "But, on January 1, the rules changed and meldonium became a prohibited substance, which I had not known."

   She added that Wada had sent her an email on December 22 informing her of changes to the banned list, but she had failed to "click" on the link that would have detailed the prohibited items.

   As for her sponsors, it remains to be seen if others follow the lead of Nike, who said it was "saddened and surprised by the news."

   Women's Tennis Association (WTA) president Steve Simon said he was "very saddened" at Sharapova's failed test. "Maria is a leader and I have always known her to be a woman of great integrity(正直)," he added. "As Maria acknowledged, it is every player's responsibility to know what they put in their body and to know if it is permissible. This matter is now in the hands of the Tennis AntiDoping Programme and its standard procedures."