WTA world No. 29 Dayana Yastremska has been given a provisional suspension by the ITF following a routine out of competition urine sample taken in November 2020

The sample contained evidence of the banned substance mesterolone , which is a synthetic form of testosterone

As it stands, this means the Ukranian cannot compete in the 2021 Australian Open due to start on 8 February, although she has a right of appeal.

The 20-year-old has protested the ruling and has vowed to clear her name, saying the low concentration was consistent with contamination, rather than doping.

“I confidently declare that I have never taken any stimulant drugs or prohibited substances,” Yastremska wrote on her social media account.

Yastremska added “I am astonished and in shock, particularly given that two weeks prior to this test – on November 9, 2020 – I tested negative at the WTA event in Linz.

“After this last tournament of the year, I stopped practicing to rest prior to the start of the new season.