Former world number nine Marin Cilic has announced that he will try to overturn the nine-month ban handed to him for a doping violation.
The International Tennis Federation confirmed the suspension yesterday, revealing that the 24-year-old ingested banned substance nikethamide inadvertently at the Munich Open in April.
"I will be appealing that decision to the Court of Arbitration for Sport very shortly," Cilic said in statement.
"I wish to emphasize that I have never knowingly or deliberately taken any banned substance in my life and that I am opposed to any use of performance-enhancing substances in sport."
The suspension has been backdated to when the original sample was taken and if Cilic's appeal fails, then the Croatian will be permitted to return to action from January 31.