Paris  - As Richard Gasquet progresses into the quarter-finals at the ATP event in Metz, his legal campaign to clear his name on cocaine drug-test charges received a minor setback when a lawsuit filed on his behalf was rejected by a court.

French prosecutors in Paris have knocked back the action by lawyers for the number-47 Frenchman as he further attempts to restore his good name in the sport.

Gasquet was pronounced free to return to tennis in July as the International Tennis Federation accepted his argument that a positive March drugs test for cocaine was the result of inadvertent exposure to the banned substance.

The 23-year-old escaped from a potential one-year ban as the tennis ruling body pronounced a ban of two and a half months. He tested positive at the Miami Masters and said that the exposure to the drug surely came from a party he attended that week.

He was provisionally suspended in May pending his appeal.

An independent anti-doping tribunal found that "while he was at fault in exposing himself to the risk of such contamination," that fault was not significant.

Elsewhere in court, the estranged father of Jelena Dokic, Damir Dokic, has had his 15-month prison sentence for threatening the Australian ambassador to Serbia confirmed in Belgrade.

Dokic, the original template for the tennis "bad dad," was found guilty in June of "endangering the security" of the ambassador after threatening to blow up the diplomat's car. (dpa)