Maria Sharapova denies receiving warnings about anti-doping rules change

She tested positive for meldonium, banned substance which she had been taking since 2006 for health issues

Former world number one Maria Sharapova dismissed suggestions that she was warned five times about changes to tennis anti-doping rules before testing positive for a banned drug at this year's Australian Open.

A defiant Sharapova said on her Facebook page that reports were inaccurate and that she had received only one clear notice in December titled 'Main Changes to the Tennis Anti-Doping Programme for 2016.'

"I should have paid more attention to it. But the other 'communications'? They were buried in newsletters, websites, or handouts," the five-time Grand Slam champion added.

She insisted that she was determined to fight back, adding that it was wrong to say that she was warned five times, Sport24 reported.

Earlier in the week, the beleaguered Russian tennis star announced that she had tested positive for meldonium, the banned substance which she had been taking since 2006 for health issues.

Meldonium was placed on the banned list by the World Anti-Doping Agency from this year.

Following the announcement, Sharapova has been provisionally suspended from the sport by the International Tennis Federation and saw major sponsors like Nike, Tag Heuer and Porsche sever ties with the Russian.