New York, March 8: Global sports apparel giants Nike has suspended ties with Maria Sharapova after the Russian tennis star failed a drug test at the Australian Open. "We are saddened and surprised by the news about Maria Sharapova,” Kejuan Wilkins, a spokesman for Nike, said on Monday. “We have decided to suspend our relationship with Maria while the investigation continues. We will continue to monitor the situation.” Sharapova disclosed at a news conference on Monday that she had been taking a drug named Meldonium for over a decade for health reasons. But the World Anti-Doping Agency (WADA) banned the drug from January 1. Sharapova, the World No.7, said she didn't notice that the drug was banned by the WADA. The International Tennis Federation (ITF) said on its website on Monday that the 28-year-old would be provisionally banned from March 12. The usual ban for first-time offenders is two years. The failed drug test came on January 26 -- after Sharapova lost to Serena Williams in the quarter-finals -- and she was charged with an anti-doping violation on March 2, the governing body additionally said. The failed drug test could cause the five-time Grand Slam winner a spot at the Rio 2016 Olympics and the $298,000 she won in January at the Australian Open.