Radoslav Karatantchev, the father and coach of Bulgarian tennis player Sesil Karatantcheva, is optimistic that her two-year drugs ban will be overturned.

The 16-year-old was banned in January after testing positive for steroids and appealed to the Court of Arbitration for Sport (CAS) in Switzerland which is expected to announce its decision today.

"Sesil has a logical explanation for the availability of norandrosterone in her system and we hope that they will understand us," Karatantchev told a news conference.

"This is sadism from a medical point of view.

"It's well known they seldom change their minds but we believe justice will win," added the former Bulgaria rowing champion.

Karatantcheva is only the second women's player to be banned for drug-taking after an independent anti-doping tribunal ruled that samples given by her at the French Open last May and out of competition in Tokyo in July contained the banned steroid nandrolone.

Karatantcheva decided to appeal, claiming that the presence of the banned substance was down to her being pregnant and the regular absorption of food supplements.

French sports daily L'Equipe reported in December that a pregnancy test carried out by a French laboratory on the player's urine sample was negative.

Karatantcheva climbed into the top 40 at the end of 2005 and reached the quarter-finals of the French Open.

"We worked really hard in the last months," added her father.

"Six experts including two lawyers and two of the top Bulgarian doctors of medicine will join us in Lausanne and I'm sure they will defend her in the best possible way."

"They believe Sesil," he said. "I can assure you that they've been working unpaid during the whole time."

Despite his optimism about the CAS decision, Karatantchev said it would not have a damaging effect on his daughter's career.

"She is still very young and we don't have to worry if the appeal is rejected.

"In two years she'll be 18 and she will have the opportunity to select the tournaments by herself."