Mellouli could lose title

Mellouli, who produced a storming swim to win the 800m freestyle in Melbourne in March with a time of 7:46.95 seconds, admits taking a tablet given to him by a fellow student at University of Southern California in Los Angeles in order to stay awake to finish an assignment.

The Tunisian federation knew about the case before the World Championships but let the 22-year-old off with a warning after accepting his explanation.

But Mellouli is now facing a possible two year ban from the sport which, as well as meaning he would be stripped of his results during the past six months, could also mean he would miss the Beijing Olympics in August next year.