Tennis Australia has been criticised for allowing banned Dayana Yastremska on a chartered flight to the Australian Open.
Yastremska, currently ranked No. 29 was provisionally suspended from all tennis activity on January 7 after allegedly failing a doping test.
World Anti-Doping Agency said a urine sample on November 24 contained a metabolite of mesterolone, a synthetic testosterone.
Yastremska has denied any offence.
“I have never used any performance-enhancing drugs or any prohibited substances,” she said on Twitter.
“I am astonished and under shock, particularly given that two weeks prior to this test, I tested negative at the WTA event in Linz.”
But former Australian Sports Anti Doping Authority chief Richard Ings blasted the decision to allow her to travel in a post on social media.
“Perhaps someone can explain to me why Ms Yastremska is on a Tennis Australia funded charter flight to Australia for the Australian Open?” he tweeted.
Tennis Australia said it was investigating the matter.