Bulgarian teenager Sesil Karatantcheva plans to appeal against a two-year ban for using performance-enhancing drugs.
The verdict was announced on Wednesday after the 16-year-old twice tested positive for banned steroid nandrolone.
"I'm going to appeal against the decision at the Court of Arbitration for Sport," she said.
Karatantcheva has claimed that the high levels of nandrolone in her system were due to a pregnancy, which later ended in miscarriage.
The ITF's independent Anti-Doping Tribunal rejected Karatatcheva's claims but the player's lawyer has high hopes that an appeal would be successful.
"We have very strong evidence, things which were not taken into account at the hearing of the tribunal," said Darina Zinovieva.
"We'll file an appeal as soon as possible, within the three-week deadline."
Karatantcheva promised to return to the sport even if she loses the appeal.
"I'll keep training, I'm only 16. I'll be back, and my return will be thunderous," she told a news conference.
The Bulgarian, who was regarded as one of the sport's rising stars, first provided a positive test at the French Open, where she beat Venus Williams before falling in the fourth round.
The second came in an out-of-competition test two months later in July.
Who is Darina Zinovieva? The pregnancy thing is odd since she tested positive in May and July according to the ITF. So she was 3 or 4 months pregnant on tour? I didn't think nandrolone was in your system at those high levels during pregnancy.
During the ban, can she become subject to new doping tests or is she free from any obligations towards the ITF/WTA during this period? Because if she knows she won't be tested for the next 2 years, then she will almost certainly use that time to continue with the doping...